7 April, 2010

Reference Guide

Advanced Routing Suite CLI

R71

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Contents

The Advanced Routing Suite ............................................................................... 13 Overview of the Advanced Routing Suite CLI .....................................................13 About this Guide .................................................................................................13 How CLI Commands are Documented in this Guide ...........................................13

Overview ........................................................................................................14 Name .............................................................................................................14 Syntax ...........................................................................................................14 Mode .............................................................................................................14 Parameters ....................................................................................................15 Description .....................................................................................................15 Default ...........................................................................................................15 Command History ..........................................................................................15 Examples .......................................................................................................15 See Also ........................................................................................................15

Using the Advanced Routing Suite CLI ............................................................... 16 Starting the Advanced Routing Suite CLI ............................................................16

The -p option .................................................................................................16 The -f option ..................................................................................................17 The -e option .................................................................................................17 The -a option .................................................................................................17 The -s option ..................................................................................................17

Basic Features ...................................................................................................18 Command Tokens .........................................................................................18 Command Line Completion............................................................................18 Moving About the Command Line ..................................................................19 Context-Sensitive Help ..................................................................................19 History ...........................................................................................................20 Disabling/Enabling CLI Tracing ......................................................................20 Aborting an Executing Command ..................................................................20 Screen Paging ...............................................................................................20 Exiting the CLI ...............................................................................................20

CLI Modes ..........................................................................................................20 User Execution M ode ....................................................................................20 Privileged Execution M ode............................................................................21 Global Configuration M ode ...........................................................................21 Router Configuration Mode ............................................................................21 Interface Configuration M ode ........................................................................21

CLI Behavior Commands....................................................................................22 configure file ..................................................................................................22 configure terminal ..........................................................................................22 disable ...........................................................................................................23 enable ............................................................................................................23 end ................................................................................................................24 exit .................................................................................................................24 ip router-id .....................................................................................................24 ip routingtable-id ............................................................................................25 logout .............................................................................................................25 quit .................................................................................................................26 show debugging .............................................................................................26 show history ...................................................................................................27 show running-config .......................................................................................28 show version ..................................................................................................29

terminal history ..............................................................................................29 terminal history size .......................................................................................30 terminal length ...............................................................................................30 write memory .................................................................................................31

Querying the Advanced Routing Suite CLI .........................................................31 Memory Information .......................................................................................31 Task Information ............................................................................................36

General Concepts ..............................................................................................38 Address and Prefix Formats ...........................................................................38 Preferences Overview ....................................................................................38 Assigning Preferences ...................................................................................39

Interfaces ............................................................................................................... 41 Interfaces Overview ............................................................................................41 autonomous-system ...........................................................................................41 disable ................................................................................................................42 preference ..........................................................................................................43 primary-alias .......................................................................................................43 unnumbered .......................................................................................................44

Kernel Interface ..................................................................................................... 46 Kernel Interface Overview ..................................................................................46 kernel background limit .......................................................................................46 kernel background priority ..................................................................................47 kernel flash limit ..................................................................................................48 kernel flash type .................................................................................................49 kernel no-change ................................................................................................50 kernel no-flush-at-exit .........................................................................................50 kernel no-install ..................................................................................................51 kernel remnant-holdtime .....................................................................................52 kernel routes.......................................................................................................53 kernel trace file ...................................................................................................54 kernel trace flag ..................................................................................................55 show kernel ........................................................................................................56

Martian Addresses ................................................................................................ 59 Martian Addresses Overview ..............................................................................59 martian ...............................................................................................................59

Multicast ................................................................................................................ 62 Multicast Overview .............................................................................................62 clear ip mroute ....................................................................................................62 ip multicast boundary ..........................................................................................63 ip multicast ttl-threshold ......................................................................................63 show ip mroute ...................................................................................................64 show ip multicast boundary ................................................................................65 show ip multicast ttl-threshold .............................................................................66

Trace Options ........................................................................................................ 67 Trace Options Overview .....................................................................................67 trace file ..............................................................................................................67 trace flag ............................................................................................................68

Border Gateway Protocol (BGP) .......................................................................... 70 Border Gateway Protocol (BGP) Overview .........................................................72 address-family ....................................................................................................76 bgp always-compare-med ..................................................................................77 bgp as-path-loops ...............................................................................................77 bgp bestpath as-path ignore ...............................................................................78 bgp bestpath compare-cluster-list-length ............................................................79 bgp bestpath compare-originator-id ....................................................................80 bgp bestpath compare-router-id..........................................................................80 bgp bestpath med confed ...................................................................................81 bgp bestpath med missing-as-worst ...................................................................82 bgp cluster-id ......................................................................................................83

bgp confederation identifier ................................................................................84 bgp confederation peers .....................................................................................84 bgp non-leading-confeds ....................................................................................85 bgp open-on-accept ............................................................................................86 bgp pass-optional-nontrans ................................................................................87 bgp restart-defer .................................................................................................88 bgp restart-delete-remnants ...............................................................................89 bgp restart-time ..................................................................................................89 bgp restart-timeout .............................................................................................90 bgp router-id .......................................................................................................91 bgp send-group-always ......................................................................................92 bgp tie-break-on-age ..........................................................................................92 clear ip bgp .........................................................................................................93 default-metric ......................................................................................................94 distance ..............................................................................................................95 distribute-list .......................................................................................................96 enable ................................................................................................................97 maximum-routes .................................................................................................98 neighbor add-communities .................................................................................99 neighbor aggregator-id .......................................................................................99 neighbor allow .................................................................................................. 101 neighbor as-loop ............................................................................................... 102 neighbor as-override ......................................................................................... 103 neighbor aspath-prepend.................................................................................. 103 neighbor capability orf comm-filter .................................................................... 104 neighbor capability orf extcomm-filter ............................................................... 105 neighbor capability orf prefix-filter ..................................................................... 106 neighbor cluster-id ............................................................................................ 107 neighbor distance ............................................................................................. 108 neighbor dynamic ............................................................................................. 109 neighbor enable ................................................................................................ 110 neighbor end-of-rib ........................................................................................... 110 neighbor export-localpref .................................................................................. 111 neighbor graceful-restart .................................................................................. 112 neighbor ignore-leading-as ............................................................................... 113 neighbor import-localpref .................................................................................. 114 neighbor keep ................................................................................................... 115 neighbor keepalives-always .............................................................................. 116 neighbor local-as .............................................................................................. 117 neighbor log-up-down ....................................................................................... 118 neighbor maximum-routes ................................................................................ 119 neighbor metric-out........................................................................................... 120 neighbor multi-protocol-nexthop ....................................................................... 121 neighbor next-hop-self ...................................................................................... 122 neighbor orf comm-list ...................................................................................... 123 neighbor orf extcomm-list ................................................................................. 124 neighbor orf prefix-list ....................................................................................... 125 neighbor out-delay ............................................................................................ 126 neighbor passive .............................................................................................. 126 neighbor password ........................................................................................... 127 neighbor pedantic ............................................................................................. 128 neighbor peer-group ......................................................................................... 129 neighbor preference2 ....................................................................................... 130 neighbor receive-buffer ..................................................................................... 131 neighbor remote-as .......................................................................................... 132 neighbor remove-private-as .............................................................................. 133 neighbor route-map .......................................................................................... 134 neighbor route-reflector-client ........................................................................... 135 neighbor route-to-peer ...................................................................................... 136

neighbor send-buffer ........................................................................................ 137 neighbor send-community ................................................................................ 137 neighbor soft-reconfiguration inbound .............................................................. 138 neighbor timers ................................................................................................. 139 neighbor ttl ....................................................................................................... 140 neighbor update-source .................................................................................... 141 neighbor use-med ............................................................................................ 142 neighbor v4-gateway ........................................................................................ 143 neighbor version ............................................................................................... 144 network ............................................................................................................. 145 preference2 ...................................................................................................... 146 redistribute ....................................................................................................... 147 router bgp ......................................................................................................... 149 show ip bgp ...................................................................................................... 149 show ip bgp instance ........................................................................................ 150 show ip bgp neighbors ...................................................................................... 151 show ip bgp orf ................................................................................................. 152 show ip bgp paths ............................................................................................ 153 show ip bgp peer-group .................................................................................... 154 show ip bgp summary ....................................................................................... 155 timers bgp ........................................................................................................ 155 trace file ............................................................................................................ 157 trace flag .......................................................................................................... 158

Internet Control Message Protocol (ICMP) ........................................................ 160 Internet Control Message Protocol (ICMP) Overview ........................................ 160 router icmp ....................................................................................................... 160 trace file ............................................................................................................ 161 trace flag .......................................................................................................... 162

Fast Open Shortest Path First (OSPF) ............................................................... 164 Fast Open Shortest Path First (OSPF) Overview .............................................. 166 router ospf ........................................................................................................ 170 advertise-subnet ............................................................................................... 171 authentication ................................................................................................... 172 compatible rfc1583 ........................................................................................... 174 dead-interval..................................................................................................... 174 distance ............................................................................................................ 175 enable .............................................................................................................. 176 enable-te .......................................................................................................... 177 hello-interval ..................................................................................................... 178 igp-shortcut ...................................................................................................... 179 inherit-metric..................................................................................................... 180 monitor-auth-key .............................................................................................. 180 multicast-rib ...................................................................................................... 181 network area..................................................................................................... 182 nssa-inherit-metric ............................................................................................ 183 nssa-stability-interval ........................................................................................ 184 poll-interval ....................................................................................................... 184 priority .............................................................................................................. 185 redistribute ....................................................................................................... 186 redistribute-nssa ............................................................................................... 188 require-vbit ....................................................................................................... 189 restart-allow-changes ....................................................................................... 190 restart-enable ................................................................................................... 191 restart-max-sync-time ....................................................................................... 192 restart-type ....................................................................................................... 193 retransmit-interval ............................................................................................. 193 router-id ............................................................................................................ 194 timers spf .......................................................................................................... 195 trace file ............................................................................................................ 196

trace flag .......................................................................................................... 197 transmit-delay ................................................................................................... 198 area advertise-subnet ....................................................................................... 199 area authentication ........................................................................................... 200 area dead-interval ............................................................................................ 202 area filter .......................................................................................................... 203 area hello-interval ............................................................................................. 204 area nssa ......................................................................................................... 205 area nssa-range ............................................................................................... 206 area nssa-translate-always ............................................................................... 207 area poll-interval ............................................................................................... 208 area priority ...................................................................................................... 209 area range ........................................................................................................ 210 area retransmit-interval ..................................................................................... 211 area stub .......................................................................................................... 212 area stubhost.................................................................................................... 213 area stubnetwork .............................................................................................. 214 area transmit-delay ........................................................................................... 215 area virtual-link ................................................................................................. 216 default-metric .................................................................................................... 217 default-nssa-metric ........................................................................................... 218 default-nssa-type .............................................................................................. 219 default-preference ............................................................................................ 219 default-tag ........................................................................................................ 220 default-type ...................................................................................................... 221 advertise-subnet ............................................................................................... 222 allow-all ............................................................................................................ 223 authentication ................................................................................................... 223 cost .................................................................................................................. 225 dead-interval..................................................................................................... 226 enable .............................................................................................................. 227 hello-interval ..................................................................................................... 228 neighbor ........................................................................................................... 229 network ............................................................................................................. 230 no-multicast ...................................................................................................... 231 passive-interface .............................................................................................. 232 poll-interval ....................................................................................................... 233 priority .............................................................................................................. 234 retransmit-interval ............................................................................................. 235 traffic-eng administrative-weight ....................................................................... 236 traffic-eng attribute-flags ................................................................................... 237 traffic-eng bandwidth ........................................................................................ 238 transmit-delay ................................................................................................... 239 ip ospf advertise-subnet ................................................................................... 240 ip ospf allow-all ................................................................................................. 241 ip ospf area ...................................................................................................... 241 ip ospf authentication ........................................................................................ 242 ip ospf cost ....................................................................................................... 244 ip ospf dead-interval ......................................................................................... 245 ip ospf enable ................................................................................................... 246 ip ospf hello-interval .......................................................................................... 247 ip ospf neighbor ................................................................................................ 248 ip ospf network ................................................................................................. 248 ip ospf no-multicast........................................................................................... 249 ip ospf passive-interface ................................................................................... 250 ip ospf poll-interval............................................................................................ 251 ip ospf priority ................................................................................................... 252 ip ospf retransmit-interval ................................................................................. 253 ip ospf traffic-eng administrative-weight ............................................................ 254

ip ospf traffic-eng attribute-flags........................................................................ 255 ip ospf traffic-eng bandwidth ............................................................................. 256 ip ospf transmit-delay ....................................................................................... 256 show ip ospf ..................................................................................................... 257 show ip ospf border-routers .............................................................................. 258 show ip ospf database ...................................................................................... 259 show ip ospf interface ....................................................................................... 260 show ip ospf neighbor ....................................................................................... 260 show ip ospf request-list ................................................................................... 261 show ip ospf retransmission-list ........................................................................ 262 show ip ospf summary-address ........................................................................ 263 show ip ospf virtual-links ................................................................................... 263

Redirect Processing ........................................................................................... 265 Redirect Processing Overview .......................................................................... 265 ip redirect ......................................................................................................... 265 router redirect ................................................................................................... 266 trace file ............................................................................................................ 266 trace flag .......................................................................................................... 267

Router Discovery ................................................................................................ 269 Router Discovery Overview .............................................................................. 269 ip router-discovery address-policy .................................................................... 270 ip router-discovery enable ................................................................................ 271 ip router-discovery trace file .............................................................................. 271 ip router-discovery trace flag ............................................................................ 272 router-discovery lifetime ................................................................................... 273 router-discovery maximum-interval ................................................................... 274 router-discovery minimum-interval .................................................................... 275

Routing Information Protocol (RIP) ................................................................... 277 Routing Information Protocol (RIP) Overview ................................................... 277 router rip ........................................................................................................... 280 default-metric .................................................................................................... 280 distribute-list ..................................................................................................... 281 ecmp ................................................................................................................ 284 enable .............................................................................................................. 284 flash-update-time .............................................................................................. 285 ignore-host-routes ............................................................................................ 286 ignore-must-be-zero ......................................................................................... 287 network ............................................................................................................. 287 preference ........................................................................................................ 288 query-authentication ......................................................................................... 289 redistribute ....................................................................................................... 290 send-updates.................................................................................................... 292 source-gateways .............................................................................................. 294 split-horizon ...................................................................................................... 295

Example 3 .................................................................................................... 296 term-updates .................................................................................................... 296 timers basic ...................................................................................................... 297 trace file ............................................................................................................ 298 trace flag .......................................................................................................... 299 trusted-gateways .............................................................................................. 300 ip rip authentication .......................................................................................... 302 ip rip enable ...................................................................................................... 303 ip rip metric-in ................................................................................................... 304 ip rip metric-out ................................................................................................. 305 ip rip no-receive ................................................................................................ 305 ip rip no-send .................................................................................................... 306 ip rip secondary-authentication ......................................................................... 307 ip rip version ..................................................................................................... 308 show ip rip database ......................................................................................... 309

Example 3 .................................................................................................... 310 SNMP Multiplexing (SMUX) ................................................................................ 312

SNMP Multiplexing (SMUX) Overview .............................................................. 312 smux password ................................................................................................ 312 smux port ......................................................................................................... 313 smux trace file .................................................................................................. 314 smux trace flag ................................................................................................. 314

Distance Vector Multicast Routing Protocol (DVMRP) ..................................... 316 Distance Vector Multicast Routing Protocol (DVMRP) Overview ...................... 316 ip dvmrp ........................................................................................................... 316 ip dvmrp distance ............................................................................................. 317 ip dvmrp default-metric ..................................................................................... 318 ip dvmrp disable ............................................................................................... 319 ip dvmrp metric-offset ....................................................................................... 319 ip dvmrp nodvmrpout ........................................................................................ 320 ip dvmrp noretransmit ....................................................................................... 321 ip dvmrp prune-lifetime ..................................................................................... 322 ip dvmrp trace file ............................................................................................. 323 ip dvmrp trace flag ............................................................................................ 324 ip dvmrp unicast-routing ................................................................................... 325 show ip dvmrp interfaces .................................................................................. 326 show ip dvmrp neighbors .................................................................................. 327 show ip dvmrp route ......................................................................................... 328 tunnel mode dvmrp ........................................................................................... 330

Internet Group Management Protocol (IGMP) ................................................... 332 Internet Group Management Protocol (IGMP) Overview ................................... 332 clear ip igmp group ........................................................................................... 333 ip igmp.............................................................................................................. 334 ip igmp ignore-v1-messages ............................................................................. 335 ip igmp ignore-v2-messages ............................................................................. 335 ip igmp last-member-query-count ..................................................................... 336 ip igmp last-member-query-interval .................................................................. 337 ip igmp query-interval ....................................................................................... 339 ip igmp query-max-response-time .................................................................... 340 ip igmp require-router-alert ............................................................................... 341 ip igmp robustness ........................................................................................... 342 ip igmp send-router-alert .................................................................................. 343 ip igmp startup-query-count .............................................................................. 344 ip igmp startup-query-interval ........................................................................... 345 ip igmp static-group .......................................................................................... 347 ip igmp trace file ............................................................................................... 348 ip igmp trace flag .............................................................................................. 349 ip igmp version ................................................................................................. 350 show ip igmp groups ......................................................................................... 351 show ip igmp interface ...................................................................................... 355 show ip igmp interface-summary ...................................................................... 358 show ip igmp static-groups ............................................................................... 359

Protocol Independent Multicast (PIM) ............................................................... 360 Protocol Independent Multicast (PIM) Overview ............................................... 360 ip pim assert-holdtime ...................................................................................... 361 ip pim dr-priority ................................................................................................ 362 ip pim hello-holdtime ......................................................................................... 363 ip pim hello-interval........................................................................................... 363 ip pim jp-holdtime ............................................................................................. 364 ip pim jp-interval ............................................................................................... 365 ip pim lan-delay ................................................................................................ 366 ip pim mrt-interval ............................................................................................. 367 ip pim mrt-stale-multiplier.................................................................................. 367 ip pim override-interval ..................................................................................... 368

ip pim triggered-hello-delay .............................................................................. 369 show ip pim control-counters ............................................................................ 370 show ip pim interface ........................................................................................ 371 show ip pim neighbor ........................................................................................ 373 Protocol Independent Multicast - Dense Mode (PIM-DM) ................................. 375

Protocol Independent Multicast - Dense Mode (PIM-DM) Overview ............. 375 ip pim dense-mode ...................................................................................... 375 ip pim graft-retry-interval .............................................................................. 376 ip pim require-genid ..................................................................................... 377 ip pim source-lifetime ................................................................................... 378 ip pim state-refresh-capable ......................................................................... 378 ip pim state-refresh-interval .......................................................................... 379 ip pim state-refresh-rate-limit ....................................................................... 380 ip pim state-refresh-ttl .................................................................................. 381 ip pim dense trace file .................................................................................. 381 ip pim dense trace flag ................................................................................. 382 show ip pim dense-mode interface-summary ............................................... 384 show ip pim dense-mode mrt ....................................................................... 384 show ip pim dense-mode mrt-summary ....................................................... 386 show ip pim grafts ........................................................................................ 387

Protocol Independent Multicast - Sparse Mode (PIM-SM) ................................ 389 Protocol Independent Multicast - Sparse Mode (PIM-SM) Overview ............ 390 ip pim associate-msdp ................................................................................. 390 ip pim bsr-admin-scope ................................................................................ 390 ip pim bsr-border .......................................................................................... 391 ip pim bsr-candidate..................................................................................... 392 ip pim bsr-candidate global .......................................................................... 393 ip pim bsr-candidate group........................................................................... 393 ip pim bsr-candidate interval ........................................................................ 394 ip pim bsr-candidate priority ......................................................................... 395 ip pim bsr-holdtime ...................................................................................... 396 ip pim dr-switch-immediate .......................................................................... 396 ip pim mrt-spt-multiplier ................................................................................ 397 ip pim probe-interval .................................................................................... 398 ip pim register-suppression-timeout ............................................................. 399 ip pim rp-address ......................................................................................... 399 ip pim rp-candidate ...................................................................................... 400 ip pim rp-candidate advertisement-interval ................................................... 401 ip pim rp-candidate group ............................................................................ 402 ip pim rp-candidate holdtime ........................................................................ 403 ip pim rp-candidate priority ........................................................................... 403 ip pim rp-switch-immediate .......................................................................... 404 ip pim sparse-mode ..................................................................................... 405 ip pim threshold ........................................................................................... 406 ip pim threshold-dr ....................................................................................... 407 ip pim threshold-rp ....................................................................................... 407 ip pim trace file ............................................................................................. 408 ip pim trace flag ........................................................................................... 410 ip pim whole-packet-checksum .................................................................... 411 show ip pim bsr-router ................................................................................. 412 show ip pim cbsr .......................................................................................... 412 show ip pim rp.............................................................................................. 413 show ip pim rp-candidate ............................................................................. 414 show ip pim rp-hash ..................................................................................... 414 show ip pim sparse-mode join-prune xmit .................................................... 415 show ip pim sparse-mode mrt ...................................................................... 415

Access Lists ........................................................................................................ 418 Access Lists Overview ...................................................................................... 418 access-list ........................................................................................................ 418

access-list sequence-number ........................................................................... 420 ip access-list sequence-number ....................................................................... 421 ip access-list standard ...................................................................................... 422 permit | deny ..................................................................................................... 422 show access-list ............................................................................................... 424 show ip access-list............................................................................................ 425

AS Paths and AS Path Lists ............................................................................... 427 AS Paths and AS Path Lists Overview.............................................................. 427 ip as-path access-list ........................................................................................ 428 ip as-path name ................................................................................................ 429 show ip as-path-access-list ............................................................................... 430 show ip bgp paths ............................................................................................ 431

BGP Communities and Community Lists ......................................................... 433 BGP Communities and Community Lists Overview .......................................... 433 ip community-list ............................................................................................... 433 ip community-set .............................................................................................. 434

Prefix Lists and Prefix Trees .............................................................................. 437 Prefix Lists and Prefix Trees Overview ............................................................. 437 ip prefix-list ....................................................................................................... 437 ip prefix-list sequence-number .......................................................................... 438 ip prefix-tree ..................................................................................................... 439 show ip prefix-list .............................................................................................. 441 show ip prefix-tree ............................................................................................ 442

Route Aggregation and Generation ................................................................... 444 Route Aggregation and Generation Overview ................................................... 444 aggregate-address ........................................................................................... 444 router aggregate ............................................................................................... 448

Route Flap Damping ........................................................................................... 449 Route Flap Damping Overview ......................................................................... 449 dampen-flap ..................................................................................................... 449 keep-history ...................................................................................................... 450 max-flap ........................................................................................................... 451 reach-decay...................................................................................................... 451 reach-tick .......................................................................................................... 452 reuse-below ...................................................................................................... 453 suppress-above ................................................................................................ 454 unreach-decay .................................................................................................. 454

Route Maps ......................................................................................................... 456 Route Maps Overview ...................................................................................... 457 match aggregate-contributors ........................................................................... 457 match as ........................................................................................................... 458 match as-path ................................................................................................... 458 match as-path-list ............................................................................................. 459 match community ............................................................................................. 460 match community-set ....................................................................................... 461 match distance ................................................................................................. 462 match extended-community-set ........................................................................ 463 match instance ................................................................................................. 464 match interface ................................................................................................. 465 match ip address access-list ............................................................................. 466 match ip address prefix-list ............................................................................... 466 match ip address prefix-tree ............................................................................. 467 match ip gateway ............................................................................................. 468 match ip next-hop ............................................................................................. 469 match ip route-source prefix-tree ...................................................................... 470 match localpref ................................................................................................. 471 match med ....................................................................................................... 471 match metric ..................................................................................................... 472 match metric-type ............................................................................................. 473

match protocol .................................................................................................. 473 match ribs ......................................................................................................... 474 match tag ......................................................................................................... 475 route-map ......................................................................................................... 476 set as-path prepend .......................................................................................... 477 set community-set ............................................................................................ 478 set dampen-flap ................................................................................................ 479 set ip next-hop .................................................................................................. 479 set local-preference .......................................................................................... 480 set med ............................................................................................................ 481 set metric .......................................................................................................... 482 set metric-type .................................................................................................. 482 set origin ........................................................................................................... 483 set preference .................................................................................................. 484 set propagate ................................................................................................... 485 set ribs .............................................................................................................. 486 set tag .............................................................................................................. 486

Index .................................................................................................................... 489

Page 13

Chapter 1

The Advanced Routing Suite

In This Chapter

Overview of the Advanced Routing Suite CLI 13

About this Guide 13

How CLI Commands are Documented in this Guide 13

Overview of the Advanced Routing Suite CLI

The Advanced Routing Suite CLI is available as part of the Advanced Networking Software Blade (http://www.checkpoint.com/products/softwareblades/advanced-networking.html).

For organizations looking to implement scalable, fault-tolerant, secure networks, the Advanced Networking blade enables them to run industry-standard dynamic routing protocols including BGP, OSPF, RIPv1, and RIPv2 on security gateways. OSPF, RIPv1, and RIPv2 enable dynamic routing over a single autonomous system—like a single department, company, or service provider—to avoid network failures. BGP provides dynamic routing support across more complex networks involving multiple autonomous systems—such as when a company uses two service providers or divides a network into multiple areas with different administrators responsible for the performance of each.

Advanced Routing is supported on the Check Point SecurePlatform operating system. For information about SecurePlatform, see the R71 SecurePlatform Administration Guide (http://supportcontent.checkpoint.com/documentation_download?ID=10313)

The Advanced Routing Suite CLI accepts user entered text commands and sends them to Advanced Routing Suite. These commands can encode a configuration change as well as queries for configuration information and dynamic protocol state.

About this Guide This guide describes the basic, protocol-independent functionality of the Advanced Routing Suite Command Line Interface (CLI), including command-line completion, logging, and history.

Advanced Routing Suite commands are listed alphabetically within protocol sections. For example, if you

are looking for the query-authentication command in RIP, look in the Routing Information Protocol

(RIP) (on page 277) chapter, then look for the command under the letter A. You can also use the Index to quickly search for a command.

How CLI Commands are Documented in this Guide

Most chapters in this guide consist of the following sections:

Overview of ... (one per chapter)

Name

How CLI Commands are Documented in this Guide

The Advanced Routing Suite Page 14

Syntax

Mode

Parameters

Description

Default

Command History

Examples

See Also

Overview Each chapter includes an Overview section. In most cases, this section describes a protocol or policy. Unlike the remaining sections, each chapter includes only one Overview section.

Name The Name section lists the name and a short description of the command. For example, the key command

in RIP:

key - sets a RIP MD5 key

Syntax The Syntax section lists the valid syntax configuration, including the no configuration (where applicable). For

example, configure the IGMP robustness to be 4 using the following syntax:

ip igmp robustness 4

Notation for parameters

In this manual, the allowed values for each parameter are listed similar to below:

Parameter: [ max-size size [ k | m ] ] ?

Parameter: address-family [ ipv4 | ipv6 ] {0,2}

The words in italics are user-entered commands that must be typed exactly as shown. The words in italics give a type of value. Some common types are size, time, or interface-name.

A pipe in a syntax (|) separates alternatives: one of them must occur. A double pipe (A || B) means that

either A or B or both must occur, in any order. Brackets ([]) are for grouping. Juxtaposition is stronger than

the double bar, and the double bar is stronger than the bar. Thus "a b | c || d e" is equivalent to "[ a b

] | [ c || [ d e ]]".

A pair of numbers in curly braces ({A,B}) indicates that the preceding type, word or group is repeated at

least A and at most B times.

Note: A question mark (?) indicates that the preceding type, word or group is optional.

Therefore, in the preceding example, specifying a max-size is optional. However, if you do specify a

max-size, you must enter a value for the size and specify either k or m.

Mode The Mode section shows the modes in which the command is valid. Some commands are valid in multiple modes. For those, the Description section details how the affects of those configurations differ in Advanced Routing Suite.

How CLI Commands are Documented in this Guide

The Advanced Routing Suite Page 15

Parameters The Parameters section lists the information that is accepted in the referenced configuration. It includes a description of what sort of parameter Advanced Routing Suite expects (for example, the number of seconds for a query), and the range of values Advanced Routing Suite expects. (For example, the startup-query interval in IGMP accepts a value between 0 and 31744.)

Note: If the parameter is a value that is user-define, such as a time or a name, then the parameter is displayed in italics (for example, time or value). If the parameter is one of several predetermined options, such as version 1, 2, or 3 in IGMP, then that parameter is displayed in bold courier new format (for example,

version 3).

Description The Description section includes a detailed description of the configuration.

Default The Default section includes the default value(s) of the command and its content.

Command History The Command History section indicates when the command was first introduced. It can also indicate whether the command, its defaults, or any of its parameters have changed.

Examples The Examples section lists valid configurations for a specified command.

See Also Some commands will include a relevant See Also section. The See Also section lists other commands or sections of this guide that might be useful. In addition, other publicly available documents, such as RFCs, may be listed here.

Page 16

Chapter 2

Using the Advanced Routing Suite CLI

In This Chapter

Starting the Advanced Routing Suite CLI 16

Basic Features 18

CLI Modes 20

CLI Behavior Commands 22

Querying the Advanced Routing Suite CLI 31

General Concepts 38

Starting the Advanced Routing Suite CLI Be sure no other users are connected to Advanced Routing Suite. With Advanced Routing Suite installed properly and running:

1. Enter the SecurePlatform expert mode.

2. Type pro enable at the prompt and press Enter.

3. Reboot.

4. Type router at the prompt and press Enter.

This begins your CLI session in User Execution mode.

The Advanced Routing Suite CLI can be started with several additional command line options. These options include the following:

-p

-f

-l

-a

-s

Note - If the CLI is given an invalid command line option, then it prints out a list of valid options, arguments for those options with a short description of each, then exits without connecting to Advanced Routing Suite.

The -p option -p <port>

The -p option specifies the port on which Advanced Routing Suite's XML subsystem is listening. The

argument to this option must be a valid port number. If the -p option is not specified, then the CLI assumes

that Advanced Routing Suite's XML subsystem is listening on port 4242.

Starting the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 17

The -f option -f <cmd_fname>

The -f option specifies a file from which CLI commands are to be read after the CLI has initialized.

The -e option -e [ ( s || c || e || w || d || i ) | 0 | all ]

The -e option specifies the event class or classes that the CLI will log. The arguments have the following meanings:

s - Trace security events

c - Trace user-typed commands

e - Trace errors

w - Trace internal warnings and errors

d - Trace debugging events

i - Trace informational events

0 - Trace no events

all - Trace all event sets

Default

If the -e option is not specified, it is the same as if -e wg were specified.

The -a option -a [ o | a | m ]

The -a option specifies the action to take if you want a log file, and a cli.log file already exists in the location

specified by the -l option. Available arguments include the following:

o - Overwrite the existing cli.log file

a - Append to the existing cli.log file

m - Move the existing cli.log file to cli.log.x, where x is the next highest integer among the other files named

cli.log.* in the logging directory.

Default

If -a is not specified, then it is as if -a a were specified.

The -s option -s <size_num>[k | m]

The -s option specifies the maximum size of the CLI log in either kilobytes or megabytes. The action to take

when the current log's maximum size is reached is determined by the -a option.

Default

If the -s option is not specified, then it is as if -s 5m were specified.

Basic Features

Using the Advanced Routing Suite CLI Page 18

Basic Features Basic features of the Advanced Routing Suite CLI include the following:

Command Tokens

Command Line Completion

Moving About the Command Line

Context-Sensitive Help

Command History

Disabling/Enabling CLI Logging

Aborting an Executing Command

Exiting the CLI

Command Tokens The Advanced Routing Suite CLI command strings are composed of space-delimited tokens. The maximum number of tokens permitted per line is 32. After a full command line is typed, the Enter key sends the line to the CLI for processing. The CLI is case insensitive.

Command Line Completion The max number of characters per line is 1024. At any point when typing a command line, you can hit the Tab key to either complete the current command token or show a list of possible completions. Consider the following command structure as an example:

abc | | -------- | | bar groove | | ------- | | par-name1 par-name2 | | number number

The valid complete command strings are the following:

abc groove

abc bar par-name1 [number]

abc bar par-name2 [number]

With command line completion, when you type

ab<Tab>

the command will be completed as abc on the same line because no other legal token begins with "ab".

When you type

abc bar <Tab>

the CLI will display the tokens that can follow bar on a separate line, then re-display your typed line as

shown below. Note that "routerz>" is the Advanced Routing Suite CLI prompt, with "routerz" being the

name of the machine on which Advanced Routing Suite is running.

routerz> abc bar <Tab> par-name1 par-name2 routerz> abc bar

Basic Features

Using the Advanced Routing Suite CLI Page 19

Note - The space between "bar" and <Tab> is required for the legal

token list to display.

Valid commands are not required to be composed of complete tokens. Only a token's smallest unique abbreviation is required. For example, the following two command strings are equivalent:

abc bar par-name1 20

a b par-name1 20

If the abbreviation is not unique, the CLI will respond with an "Invalid command" error.

Moving About the Command Line The curser does not need to be at the end of a command line before hitting the Enter key. In the examples below, the underscore indicates the position of the curser.

routerz> abc bat bas_

If, in the example above, you intended to type "abc bar bas", move the left arrow key back to the space following "bat", delete the "t", and type "r".

routerz> abc bar_bas

With the curser still just right of the "r", you can still hit the ENTER key, and the complete line will be given to the CLI for processing.

Context-Sensitive Help Type "?" immediately after any token to obtain context-sensitive help about the last command that you typed. For example requesting help immediately after typing "router" shows you that the command enters router mode:

(config)#router?

router Enter router mode

Type "?" followed by a space after any set of tokens to obtain a list of options that can be used in the command. For example, if you type the following:

(config)# router ?

the CLI will respond with the following:

aggregate Configure Aggregate/Generate routes bgp Configure BGP icmp Configure ICMP ospf Configure OSPF rip Configure RIP

(config)# router

If "router" was not a valid sequence of tokens (or, if it was misspelled), then the CLI would respond with

an "Error completing word" error.

Note - Because the "?" special character is used for Help, it cannot be included in any character string. In other words, a "?" cannot be used when configuring a route map name, a prefix list name, and so on. Doing so will display Help for the command, as shown in the example below.

(config)#access-list an?

<name> Name of an access list

CLI Modes

Using the Advanced Routing Suite CLI Page 20

History All commands entered during a CLI session are saved in a command history. The command history can be viewed and with short-hand "!" commands. The history can be toggled on and off.

Disabling/Enabling CLI Tracing The CLI provides a flexible tracing mechanism. Events to be traced are divided into several classes, each of which can be traced individually. Classes can be traced to any or all three of the following locations: the terminal, a file, or the underlying system's tracing system (i.e., syslog).

Aborting an Executing Command It may sometimes be desirable to abort a query that generates a lot of output. Typing Ctrl+C generates such an abort signal and flushes any queued input.

Screen Paging If a response to a command contains more lines than provided by the command line window, then the word "more" appears at the bottom of the screen to indicate that not all lines have been displayed. Press the Space bar to display more lines. To stop viewing the output and return to the command line prompt, press any other key.

Exiting the CLI Changes are saved as soon as you hit "Enter" after a command. Use the "quit" command to exit the CLI.

CLI Modes The Advanced Routing Suite CLI has the following five modes:

User Execution

Privileged Execution

Global Configuration

Router Configuration

Interface Configuration

The current mode is easily discerned by examining the current command line prompt. The CLI prompt always indicates the current mode. The modes and prompts are described in the sections that follow.

User Execution M ode User Execution mode is the default mode that the CLI assumes when it begins execution. In User Execution

mode, the prompt is ">".

Note - If the CLI is started with the "-f <cmd_fname>" parameter

(see The -f option on page 17 for more information), then the

commands contained in cmd_fname could leave the CLI in something

other than User Execution mode when command-line entry control is turned over to the user.

Within User Execution mode, the following actions are allowed:

Querying of Advanced Routing Suite configuration state

Querying of dynamic protocol state (for example, the number of OSPF neighbors)

CLI Modes

Using the Advanced Routing Suite CLI Page 21

Modification of various CLI options, such as command history length, CLI events to trace, and so on.

Privileged Execution M ode Privileged Execution mode allows for "privileged" commands. In Privileged Execution mode, the prompt is

"#". This mode is password protected and is entered using enable as follows:

routerz> enable Password: [password] routerz#

Note - The CLI allows three attempts at the "Password:" prompt

before returning to the ">" prompt.

Use the disable command to leave Privileged Execution mode and return to User Execution mode.

Global Configuration M ode Global Configuration mode is used to change the configuration of Advanced Routing Suite. From this mode, you can stop and start protocols and set protocol-specific parameters. This mode can only be entered from

Privileged Execution mode with the configure terminal command. When this mode is entered, the

prompt changes to "(config)#" as shown below.

routerz> enable Password: [password] routerz# configure terminal routerz(config)#

Unless otherwise noted, configuration changes that are entered in this mode are made immediately upon

hitting Enter.

To exit Global Configuration mode and return to Privileged Execution mode, use the "exit" or "end"

command or type "Ctrl+Z". All three are synonymous.

routerz(config)# end routerz#

Router Configuration Mode Router Configuration mode is used to change the protocol state on a specific router. This mode is entered

by typing the following at the (config)# prompt:

router protocol_name

For example, type the following to enter Router Configuration mode for the ICMP protocol:

routerz(config)# router icmp routerz(config-icmp)#

The prompt changes to "(config-[protocol_name])#" in Router Configuration mode. To exit Router

Configuration mode and return to Global Configuration mode, use the "exit" command.

routerz(config-icmp)# exit routerz(config)#

Interface Configuration M ode Interface Configuration mode is used to change protocol state on a specific interface. This mode is entered

by typing the following at the (config)# prompt:

interface [ if-type if-number | if-name ]

For example, type the following to enter Interface Configuration mode for the physical interface named ppp-interface-0:

routerz(config)# interface ppp-interface-0 routerz(config-if)#

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 22

The prompt changes to "(config-if)#" in Interface Configuration mode. To exit Interface Configuration mode

and return to Global Configuration mode, use the "exit" command.

routerz(config-if)# exit routerz(config)#

CLI Behavior Commands The section describes the commands that control the CLI behavior, as opposed to commands that control Advanced Routing Suite behavior.

configure file

Syntax

configure file [filename | replace filename]

Mode

Privileged Execution

Parameters

filename - the name and/or path of the configure file

replace filename - specifies to replace the current configuration file with the specified filename

Description

The configure file command is used to enter an atomic batch mode, where configuration commands

are read from the named file or replace with the named file. If any errors are encountered during processing

of the named file, then the router's configuration is left unchanged. The filename argument to file can

be either a fully or partially qualified name. A fully qualified file name begins with "/" and gives the complete

path to the file in addition to the file name. A partially qualified file name does not begin with"/" and may

indicate path information in addition to the file name. If path information is given, it is interpreted with respect to the CLI's working directory.

Examples

In the following example, configuration commands are read from the file, /etc/routerz.cfg.

routerz# configure file /etc/routerz.cfg routerz#

configure terminal

Syntax

configure terminal

Mode

Privileged Execution Mode

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 23

Description

Use the configure terminal command in Privileged Execution mode to enter Global Configuration mode

and change the router's configuration. This command takes one of two parameters. The "#" prompt changes

to "(config)#" to indicate the changed mode. Use the "end" command to leave Global Configuration

mode.

Examples

In the following example, configuration commands are entered from the terminal.

routerz# configure terminal routerz(config)# terminal history size 1024 routerz(config)# end routerz#

disable

Syntax

disable

Mode

Privileged Execution

Description

Use the disable command to leave Privileged Execution Mode and re-enter User Execution mode.

Examples

routerz# disable routerz>

enable

Syntax

enable

Mode

User Execution

Description

Use the enable command to enter Privileged Execution mode from User Execution mode. The # prompt

indicates that the current mode is Privileged Execution mode.

Note - A password is required to enter Privileged Execution mode.

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 24

Examples

routerz> enable Password: abcdefg routerz#

end

Syntax

end

Mode

Global Configuration

Description

Use the end command to leave Global Configuration mode and return to Privileged Execution mode.

Examples

routerz(config)# end routerz#

exit

Syntax

exit

Mode

Interface Configuration

Global Configuration

Description

Use the exit command to leave Interface Configuration mode and return to Global Configuration mode. Or,

use exit to leave Global Configuration mode and return to Privileged Execution mode. Finally, use exit to

leave Router Configuration mode and return to Global Configuration mode.

Examples

routerz(config-if)# exit routerz(config)#

or

routerz(config)# exit routerz#

ip router-id

Syntax

ip router-id ipv4 address

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 25

Mode

Global Configuration

Parameters

ipv4_address - a valid IPv4 address

Description

Use the ip router-id command to configure the global Router ID. This router ID can be overridden in

BGP, OSPF, and OSPF3.

Examples

routerz(config)# ip router-id 1.1.1.1 routerz(config)#

ip routingtable-id

Syntax

ip routingtable-id id

Mode

Global Configuration

Parameters

id - an integer from 0 to 250, inclusive

Description

Use the ip routingtable-id command to configure an ID for the routing table. When there is no kernel

VRF support, this ID is used to decide the kernel routing table to which Advanced Routing Suite will write.

Examples

routerz(config)# ip routingtable-id 200 routerz(config)#

logout

Syntax

logout

Mode

User Execution

Description

Use the logout command to exit the CLI. This command is synonymous with exit.

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 26

Examples

The following example logs you out of the CLI.

Note - The "%" prompt is intended to indicate the shell command line

prompt. The prompt can be different, depending on the shell and shell settings from which the Advanced Routing Suite CLI was started.

routerz> logout %

quit

Syntax

quit

Mode

User Execution

Description

Use the quit command to exit the CLI. This command is synonymous with logout.

Examples

The following example exits you out of the CLI. Note that the "%" prompt is intended to indicate the shell

command line prompt. The prompt can be different, depending on the shell and shell settings from which the Advanced Routing Suite CLI was started.

routerz> quit %

show debugging

Syntax

show debugging

Mode

User Execution

Privileged Execution

Global Configuration

Interface Configuration

Description

This command is used to report information that is of use mainly to developers.

Examples

routerz> show debugging ...debugging output... routerz>

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 27

show history

Syntax

show history

Mode

User Execution

Privileged Execution

Global Configuration

Interface Configuration

Description

Use show history in any mode to display the commands that have been entered during the current

session. The format of the history lines is as follows:

command number time-stamp command

command number represents the sequential number of the command. The most recent command displays

with the highest number. time-stamp displays the time when the command was entered. Finally, command

shows the command that was entered.

To re-run the most recent command, type !!, and press Enter.

To re-run a specific command appearing in the history list, type !<number>, where <number> is the

command number as it appears in the output of a show history command.

Examples

Example 1

In the following example, several commands are entered. The command history is then displayed.

routerz> enable Password: abcdefg routerz# configure terminal routerz(config)# interface fxp0 routerz(config-if)# ip igmp robustness 2 routerz(config-if)# show history 0 09:15:02 enable 1 09:15:48 configure terminal 2 09:16:12 interface fxp0 3 09:17:03 ip igmp robustness 2 4 09:17:50 show history routerz(config-if)#

Example 2

In the following example, several commands are entered, followed by a show history command. Finally, a

short-hand ! command is used to re-run a previous command.

routerz> enable Password: abcdefg routerz# configure terminal routerz(config)# interface fxp0 routerz(config-if)# ip rip metric-in 2 routerz(config-if)# Ctrl+z routerz# show history 0 10:24:10 enable 1 10:25:17 configure terminal

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 28

2 10:26:48 interface fxp0 3 10:27:08 ip rip metric-in 2 4 10:28:00 Ctrl+z 5 10:28:22 show history routerz(config-if)# !3

show running-config

Syntax

show running-config

Mode

Privileged Execution

Description

The show running-config command reports the active configuration.

Examples

The following example shows output for a request for all configuration information.

routerz# show running-config Building configuration...

Current configuration : 966 bytes ! version 12.2 service password-encryption ! hostname router-abc ! enable password 7 011204070A59554E ! ip subnet-zero !! ip multicast-routing ! interface Ethernet0/0 ip address 10.139.10.26 255.128.0.0 ip pim bsr-border ip pim sparse-mode half-duplex ! interface Serial0/0 ip address 10.11.41.21 255.255.255.252 ! interface Ethernet0/1 ip address 10.11.111.26 255.255.255.0 ip pim sparse-mode ! router ospf 7 log-adjacency-changes ! router bgp 7 bgp log-neighbor-changes ! ip default-gateway 10.254.10.1 ip classless ip route 0.0.0.0 0.0.0.0 10.254.10.1

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 29

no ip http server ip ospf name-pookup ! access-1ist 1 permit 224.0.0.0 15.255.255.255 ! !end

routerz#

show version

Syntax

show version

Mode

User Execution

Privileged Execution

Description

This command displays the version of the Advanced Routing Suite CLI as well as the version of Advanced Routing Suite.

Examples

The following example is a request to determine the version of Advanced Routing Suite currently running.

routerz> show version CLI version: 1.1

GateD version: ngc 2.3

AMI API version: 2 routerz>

terminal history

Syntax

terminal history

terminal no history

Mode

User Execution

Privileged Execution

Global Configuration

Interface Configuration

Description

The terminal history command can be used in any mode to turn on command line history. The

terminal no history command turns off command line history.

CLI Behavior Commands

Using the Advanced Routing Suite CLI Page 30

Examples

In the following example, command line history is turned on with the first command. Several commands are then entered, followed by a command to turn the command line history off.

routerz> terminal history routerz> configure terminal routerz(config)# interface 10.10.11.1 routerz(config-if)# ip dvmrp metric-offset in 2 routerz(config-if)# exit routerz(config)# interface fxp0 routerz(config-if)# ip rip metric-in 1 routerz(config-if)# exit routerz(config)# terminal no history

terminal history size

Syntax

terminal history size num-lines

Mode

User Execution

Privileged Execution

Global Configuration

Interface Configuration

Description

Use the terminal history size command in any mode to set the maximum number of lines that are

remembered in the command line history. The default size of the command line history buffer is 1000 lines. The valid range is from 0 to 10,000, inclusive.

Examples

The following example sets the command line history buffer to 10 lines.

routerz> terminal history size 10

terminal length

Syntax

terminal length num-lines

Mode

User Execution

Privileged Execution

Global Configuration

Interface Configuration

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 31

Description

Use the terminal length command in any mode to specify the number of lines that display on a page.

The number of lines defaults to the length of your screen. The valid range for length is 0 to 4,294,967,295,

inclusive.

Note

- Specifying 0 for length sets the terminal length to infinity

If the number of lines specified is less than the number of lines to be displayed, the output for the remaining lines will display in the interactive pager similar to the following:

-- MORE (<space> = next page; <enter> = next line; <Q>

= stop) --

Examples

The following example sets the number of displayed lines to 40 lines.

routerz> terminal length 40

write memory

Syntax

write memory

Mode

Privileged Execution

Description

Use the write memory command in Privileged Execution mode to write the current Advanced Routing

Suite config file for use at startup.

Examples

The following example configures write memory.

routerz# write memory

Querying the Advanced Routing Suite CLI Use the Advanced Routing Suite queries to request information about a CLI session. Both the candidate and the committed configurations can be queried at any time during a CLI session. Unless otherwise specified, queries can be issued for the entire configuration hierarchy or a subtree of the hierarchy. Protocol-specific query information is available in each chapter. Queries can also be performed to determine memory and task information.

Memory Information Use the show memory query to obtain information about Advanced Routing Suite's current memory usage.

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 32

Syntax

show memory

Parameters

none

Description

The show memory query displays information about Advanced Routing Suite's current memory usage.

Examples

The following example displays a response for the show memory query.

> show memory

Block Name: "nospf_if_head_t" Block Size: 4 Freelist Length: 1005 Num Init Requests: 1 Num Alloc Requests: 0 Num Free Requests: 0 Num blocks in use: 0 Num bytes in use: 0

Total bytes consumed: 56516 Total bytes in use: 159692 Num block alloc calls: 53767 Min used block size: 4 Page size: 4096 Num of pages allocated: 4096 Num task block malloc pages: 155 Num task block alloc pages: 28 Multipage max alloc: 41 Multipage max reused: 86 Task page alloc multiq: 5 Task block reclaim shreds: 0 Task block reclaim unmaps: (null) Num multipage pages in use: 95 Num pool alloc pages: 0 Growable array information: Num of growable arrays: 33 Num of growths: 7 Max allocation: 256 Num malloc calls: 1400 Num calloc calls: 7 Num reallocs: 2532 Num reallocs for more: 11462 Num reallocs for less: 27 Num reallocs for same: 8 Num free-calls: 8 Num bytes requested: 0 Num bytes allocated: 0 Num bytes wasted: 11240 Max outstanding allocs: 41932 Max request: 59848 Num outstanding allocs: 17632

Field Descriptions

The following table describes the fields that appear in the Show Memory Query.

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 33

Table 2-1 Show Memory Query Fields

Field Description

Block Name The name associated with this block allocator.

Block Size This value shows the size, in bytes, of each block allocated by the block memory allocator. Its value is a non-negative integer.

Freelist Length This value indicates the length of the freelist associated with the block memory allocator. Its value is a non-negative integer. This information is useful mostly to developers.

Num Init Requests This value shows the number of times that a block memory allocator has been initialized. Its value is a non-negative integer. This information is useful mostly to developers.

Num Alloc Requests This value indicates the number of block memory allocation requests that a block memory allocator has received. Its value is a non-negative integer. This information is useful mostly to developers.

Num Free Requests This value indicates the number of block memory free requests that a block memory allocator has received. Its value is a non-negative integer. This information is useful mostly to developers.

Num blocks in use This value indicates the number of memory blocks that are currently outstanding (or in use) for a memory block allocator. Its value is a non-negative integer.

Num bytes in use This value indicates the number of bytes that are currently outstanding (or in use) for a block memory allocator. This value is equal to the value of block-size multiplied by the value of num-blocks-in-use and is always a non-negative integer.

Total bytes consumed This value indicates the number of bytes that are associated with all block memory allocators, either in use or freed. Its value is a non-negative integer.

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 34

Field Description

Total bytes in use This value indicates the number of bytes that are outstanding from all block memory allocators. This is different from the value of total-bytes-consumed, which represents the number of bytes in use or freed summed over all block memory allocators.

Num block alloc calls This value is a non-negative integer. This information is useful mostly to developers.

Min used block size This value is a non-negative integer. This information is useful mostly to developers.

Page size This value is a non-negative integer. This information is useful mostly to developers.

Num of pages allocated This value is a non-negative integer. This information is useful mostly to developers.

Num task block malloc pages This value is a non-negative integer. This information is useful mostly to developers.

Num task block alloc pages This value is a non-negative integer. This information is useful mostly to developers.

Multipage max alloc This value is a non-negative integer. This information is useful mostly to developers.

Multipage max reused This value is a non-negative integer. This information is useful mostly to developers.

Task page alloc multiq This value is a non-negative integer. This information is useful mostly to developers.

Task block reclaim shreds This value is a non-negative integer. This information is useful mostly to developers.

Task block reclaim unmaps This value is a non-negative integer. This information is useful mostly to developers.

Num multipage pages in use This value is a non-negative integer. This information is useful mostly to developers.

Num pool alloc pages This value is a non-negative integer. This information is useful mostly to developers.

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 35

Field Description

Growable array information This value is a non-negative integer. This information is useful mostly to developers.

Num of growable arrays This value is a non-negative integer. This information is useful mostly to developers.

Num of growths This value is a non-negative integer. This information is useful mostly to developers.

Max allocation This value is a non-negative integer. This information is useful mostly to developers.

Num malloc calls This value is a non-negative integer. This information is useful mostly to developers.

Num calloc calls This value is a non-negative integer. This information is useful mostly to developers.

Num reallocs This value is a non-negative integer. This information is useful mostly to developers.

Num reallocs for more This value is a non-negative integer. This information is useful mostly to developers.

Num reallocs for less This value is a non-negative integer. This information is useful mostly to developers.

Num reallocs for same This value is a non-negative integer. This information is useful mostly to developers.

Num free-calls This value is a non-negative integer. This information is useful mostly to developers.

Num bytes requested This value is a non-negative integer. This information is useful mostly to developers.

Num bytes allocated This value is a non-negative integer. This information is useful mostly to developers.

Num bytes wasted This value is a non-negative integer. This information is useful mostly to developers.

Max outstanding allocs This value is a non-negative integer. This information is useful mostly to developers.

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 36

Field Description

Max request This value is a non-negative integer. This information is useful mostly to developers.

Num outstanding allocs This value is a non-negative integer. This information is useful mostly to developers.

Task Information Use the show task query to obtain information about currently active Advanced Routing Suite tasks.

Syntax

show task

Parameters

none

Description

The show task query displays information about currently active Advanced Routing Suite tasks.

Note - Obtaining information about a specific task is not supported.

Examples

The following example displays a response for the show task query.

> show task

Task Name: "IF" Task Proto Number: N/A Task Priority: 10 Task Address: N/A Task Port: N/A Task Socket: N/A Task RT Proto Bit: Direct Task Flags: Accept: no Connect: no Delete: no Low-Priority: no

Field Descriptions

The following table describes the fields that appear in the Show Memory Information Query.

Table 2-2 Show Memory Information Query Fields

Field Description

Task Name The name of the task in double quotes

Querying the Advanced Routing Suite CLI

Using the Advanced Routing Suite CLI Page 37

Field Description

Task Proto Number The Advanced Routing Suite internal protocol number. This number has no direct correspondence to any type of protocol number carried in a data packet. Its value is a non-negative integer. This information is useful mostly to developers.

Task Priority Shows the priority of the Advanced Routing Suite task. This priority is used to schedule various task-specific operations. Its value is a non-negative integer. This information is useful mostly to developers.

Task Address The ipv4 address that is associated with this task

Task Port The port number associated with this task. Typically, only tasks associated with connection-oriented protocols will have a port number of 0 or greater. For all other tasks, the value of this tag is -1.

Task Socket The socket number associated with the task. Typically, only tasks associated with connection-oriented protocols will have a port number of 0 or greater. For all other tasks, the value of this tag is -1.

Task RT Proto Bit The task's RTRPROTO bit. This name is always contained in double quotes. This information is useful mostly to developers.

Task Flags A field for all flags associated with a task

Accept Shows the setting for the TASKF_ACCEPT bit for the indicated task. This bit is set if the task is accepting incoming connections. There are some tasks for which this bit is never set. This flag is useful mostly to developers.

Connect Shows the setting for the TASKF_CONNECT bit for the indicated task. This bit is set if the task's socket is in connected state. There are some tasks for which this bit is never set. This flag is useful mostly to developers.

General Concepts

Using the Advanced Routing Suite CLI Page 38

Field Description

Delete Shows the current setting of the TASKF_DELETE bit for the indicate task. This bit is set if the task has been marked for deletion.

Low Priority Shows the setting for the TASKF_LOWPRIOR bit for the indicated task. If this flag is on, it indicates that the task runs at a lower priority than other tasks. This flag is useful mostly to developers.

General Concepts

Address and Prefix Formats Advanced Routing Suite allows configuration of IPv4 address types only. Normally Advanced Routing Suite can recognize which type of address is being configured in a particular instance by the format of the address.

IPv4 addresses are 32 bits long. The formats of Ipv4 addresses recognized by Advanced Routing Suite are:

d

d.d

d.d.d

d.d.d.d

where d represents a number in the range 0-255 inclusive. Each d specifies 8 bits of the address. If fewer

than four d values are provided then the values provided specify the high order values of the address. For

example, 192.168 is equivalent to 192.168.0.0.

In many cases IPv4 addresses are combined with masks to configure prefixes. There are two methods for

specifying the mask: It can be specified as an IPv4 address proceeded by the mask keyword; or it can be

specified as a length proceeded by the masklen keyword or, more conventionally, by a '/'. In the "mask"

case, the address type of the mask must match the address type. Currently only contiguous bit masks are allowed in Advanced Routing Suite. Any non-zero address bits in positions that are covered by the specified mask cause a parse error. Example prefix specifications are:

10/8

10.0.0.0 mask 255.0.0.0 (equivalent to 10/8)

10 masklen 8 (equivalent to 10/8)

0/0 (IPv4 default address)

192.168.1/16 (invalid because the .1 is not covered by the mask)

Preferences Overview Preference is the value that Advanced Routing Suite uses to select one route over another when more than one route to the same destination is learned from different protocols or peers. Preference can be set in the Advanced Routing Suite configuration files in several different configuration statements. Preference can be set based on one network interface over another, one protocol over another, or one remote gateway over another. Preference cannot be used to control the selection of routes within an interior gateway protocol. This control is accomplished automatically by the protocol based on metric. Preference can be used to select routes from the same exterior gateway protocol (such as BGP) learned from different peers or autonomous systems. Each route has only one configurable preference value associated with it, even

General Concepts

Using the Advanced Routing Suite CLI Page 39

though preference can be set at many places in the configuration file. Simply, the last or most specific preference value set for a route is the value used. Preference can also be used to select one IGP instance over another.

The preference value is an arbitrarily assigned value used to determine the order of routes to the same

destination in a single routing database. The active route is chosen by the lowest preference value. Some

protocols implement a second preference (preference2), sometimes referred to as a tie-breaker. BGP

and OSPF protocols use preference2. For OSPF, preference2 is for internal use only and is not

configurable. For BGP, preference2 can be configured. Its value is used only when comparing routes with

equal values of preference.

Assigning Preferences A default preference is assigned to each source from which Advanced Routing Suite receives routes. Preference values range from 1 to 255, with the lowest number indicating the most preferred route.

Note - The default preference for direct routes (i.e., routes to subnets on directly connected interfaces) is 0. Other sources from which Advanced Routing Suite receives routes (i.e., OSPF) cannot be set to 0. The lowest preference value that can be specified for these is 1.

The following table summarizes the default preference values for routes learned in various ways. The table lists the statements (some of which are clauses within statements) that set preference and shows the types of routes to which each statement applies. The table lists the preference precedence between protocols and the default preference for each type of route. The more narrow the scope of the statement, the higher the precedence its preference value is given, but the smaller the set of routes it affects.

Table 2-3 Preference Selection Precedence

Preference of Defined by Statement Default

Directly connected networks interface 0

Routes to interface aliases 1

OSPF routes ospf 10

Redirects redirect 30

Routes learned via route socket

kernel 40

Routes installed via SNMP 50

Routes learned via router discovery

router-discovery 55

RIP routes rip 100

Point-to-point interface 110

Routes to interfaces that are down

interface 120

Aggregate/generate routes aggregate/generate 130

OSPF AS external routes ospf/ospf3 150

BGP routes bgp 170

Routes in kernel at startup 254

General Concepts

Using the Advanced Routing Suite CLI Page 40

Page 41

Chapter 3

Interfaces

In This Chapter

Interfaces Overview 41

autonomous-system 41

disable 42

preference 43

primary-alias 43

unnumbered 44

Interfaces Overview Use interface commands to configure globally scoped interface parameters. With these commands, you can override system defaults for sets of interfaces. Both physical and logical interfaces can be individually identified and their global parameters set. In addition, sets of physical interfaces can be specified by way of a "wildcarding" mechanism.

autonomous-system

Name

autonomous-system - specifies the autonomous system (AS) used to create an AS path associated with

the interface route created from this interface

Syntax

autonomous-system as-number

no autonomous-system as-number?

Mode

Interface Configuration

Parameters

as-number - an integer between 1 and 65535, inclusive

Description

The autonomous-system command specifies the autonomous system that will be used to create an AS

path associated with the route created from the definition of this interface. The autonomous system number of the router running Advanced Routing Suite is specified with the global AS command. The autonomous system numbers of BGP's peers is specified in BGP configuration. An interface defines a route known as an "interface route". Interface routes are also known as direct routes. Specifying an AS number on the interface will cause the direct route corresponding to the interface to be generated with a non-empty AS path. If this route is then exported into BGP, update messages advertising this route will include the specified AS in their AS path. Normally, the interface AS number is not set.

disable

Interfaces Page 42

The negative of this command, no autonomous-system, removes the autonomous-system definition

previously defined by the autonomous-system command and reverts to the default of no

autonomous-system associated with this interface. Note: Specifying a value for as-number in the no form

has no effect on the configuration. Thus, it is displayed above as optional.

Default

By default, no AS number is associated with an interface.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example sets the AS for interface fxp1 to be 1439.

(config)# interface fxp1

(config-if)# autonomous-system 1439

disable

Name

disable - disables the associated interface

Syntax

disable

no disable

Mode

Interface Configuration

Parameters

none

Description

The disable command specifies that messages received on this interface must be ignored. The negative

of this command, no disable, re-enables the interface.

Default

This option is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables inter face 192.168.15.1

(config)# interface 192.168.15.1

(config-if)# disable

preference

Interfaces Page 43

preference

Name

preference - used to select the best route when multiple routes exist for the same destination

Syntax

preference pref

no preference pref?

Mode

Interface Configuration

Parameters

pref - an integer in the range of 0 to 255 inclusive, with 0 being the highest preference that a route may

have. Note: Only direct routes (in other words, routes to subnets on directly connected interfaces) can have a preference of 0.

Description

Multiple routes can exist for the same destination prefix. In this situation, the route's preference is used to

select the best route. For interface routes, preference sets the preference for routes to this interface when

it is up.

The negative of this command, no preference, removes the configured preference and reverts to the

default preference of 0. Note: Specifying a value for pref in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If preference is not configured, it is as if the user had configured the following:

(config-if)# preference 0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example sets the preference for interface fxp1 to be 15.

(config)# interface fxp1

(config-if)# preference 15

primary-alias

Name

primary-alias - sets the primary logical address for a physical interface

Syntax

primary-alias [ ipv4-addr ipv4-address masklen len | no primary-alias [ ipv4-addr ipv4-address masklen len |

Mode

Interface Configuration

unnumbered

Interfaces Page 44

Parameters

ipv4-addr ipv4-address masklen len - specifies an IPv4 address with a netmask. The value of len

can be a number from 0 to 32, inclusive

Description

The primary-alias command is used to override the default selection of the primary logical interfaces on

a given physical interface. There is exactly one primary interface for each subnet defined on a given physical interface. By default, Advanced Routing Suite selects the first logical read from the operating

system for each subnet defined on the physical interface as a primary interface. The primary-alias

command provides a way to specify which of the logical interfaces that share the same subnet is to be selected as primary for that subnet.

The negative of this command, no primary-alias removes the configured primary-alias command and

reverts to the default primary addresses, which are the addresses of the first interfaces read from the kernel

for each subnet on a physical interface. Note: Specifying parameters after no primary-alias has no

effect on the configuration. Thus, they are displayed above as optional.

Default

The default primary addresses are the addresses of the first interfaces read from the kernel for each subnet on a physical interface.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures physical interface fxp1 and sets the primary-alias for that physical

interface to 192.168.10.15 with a mask length of 24.

(config)# interface fxp1

(config-if)# primary-alias ipv4-addr 192.168.10.15 masklen 24

unnumbered

Name

unnumbered - configures the specified interface as an unnumbered interface

Syntax

unnumbered interface-name

no unnumbered interface-name

Mode

Interface Configuration

Parameters

interface-name - the name of the physical interface from which an interface address will be borrowed

Description

The unnumbered command indicates that the associated interface is an "unnumbered" interface. The

purpose of unnumbered interfaces is to allow a network administrator to save IP address space. There are, by definition, only two machines on a serial or ppp link, and having to assign an IP subnet is an inefficient use of IP address space. In order to forward packets, a host or router must have an IP source address.

The IPv4 address of the first primary logical interface on the physical interface named by the interface-name parameter will be borrowed and used for the interface named in this command.

unnumbered

Interfaces Page 45

The term, "Unnumbered Interface" is actually a misnomer. The interfaces are not really unnumbered. What actually happens is the unnumbered interface borrows an IP address from another configured interface on the box to use as its source address.

With regards to unnumbered interfaces, the following assumptions are made:

The p2p or serial link has a framing protocol for encapsulating IP packets (such as PPP or HDLC).

The operating system provides a method for joining a multicast group on a physical interface by referring to the interface by name (such as "ppp1") or interface index.

A supporting physical interface exists on the box that is configured with a valid IP address.

A route can be installed in the OS forwarding table with a nexthop address of 0 or a nexthop specifying the physical interface.

The negative of this command, no unnumbered, removes the unnumbered definition previously configured

with the unnumbered command and reverts to the default of the interface being a numbered interfaces.

Default

Interfaces are not unnumbered by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures interface eth0 as an unnumbered interface.

(config)# interface eth0

(config-if)# unnumbered eth1

Page 46

Chapter 4

Kernel Interface

In This Chapter

Kernel Interface Overview 46

kernel background limit 46

kernel background priority 47

kernel flash limit 48

kernel flash type 49

kernel no-change 50

kernel no-flush-at-exit 50

kernel no-install 51

kernel remnant-holdtime 52

kernel routes 53

kernel trace file 54

kernel trace flag 55

show kernel 56

Kernel Interface Overview Although the kernel interface is not technically a routing protocol, it has many characteristics of one, and Advanced Routing Suite handles it similarly. The routes Advanced Routing Suite chooses to install in the kernel forwarding table are those that will actually be used by the kernel to forward packets.

The add, delete, and change operations that Advanced Routing Suite must use to update the typical kernel forwarding table take a non-trivial amount of time. The time used does not present a problem for older routing protocols (such as RIP), which are not particularly time critical and do not easily handle large numbers of routes anyway. The newer routing protocols (such as OSPF and BGP) have stricter timing requirements and are often used to process many more routes. The speed of the kernel interface becomes critical when these protocols are used.

To prevent Advanced Routing Suite from locking up for significant periods of time while installing large numbers of routes (up to a minute or more has been observed on real networks), the processing of these routes is done in batches. The size of these batches can be controlled by the tuning parameters shown below, but normally the default parameters will provide the proper functionality.

During normal shutdown processing, Advanced Routing Suite deletes all the routes it has installed in the

kernel forwarding table, except for those static routes marked with flag-retain. (See Chapter 8 (Static

Routes) for more information.) Optionally, Advanced Routing Suite can leave all routes in the kernel

forwarding table by not deleting any routes using no-flush-at-exit. This option is useful on systems

with large numbers of routes because it eliminates the need to re-install the routes when Advanced Routing Suite restarts, which can greatly reduce the time it takes to recover from a restart.

kernel background limit

Name

kernel background limit - specifies the type of routes that will be processed during a flash update

kernel background priority

Kernel Interface Page 47

Syntax

kernel background limit number

no kernel background limit number?

Mode

Global Configuration

Parameters

number - specifies a number of routes that can be processed during one batch. The valid value range is 0

to 4,294,267,295, inclusive.

Description

Because only interface routes are normally installed during a flash update, the remaining routes are processed in batches in the background, that is, when no routing protocol traffic is being received. The

kernel background limit command specifies how these batches are processed.

The negative of this command, no kernel background limit, reverts back to the default of maximum of

120 routes of lower priority. Note: Specifying a value for number in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

if kernel background is not specified, it is the same as if the user had specified the following:

(config)# kernel background limit 120

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, the number of background route updates is limited to 40 routes.

(config)# kernel background limit 40

kernel background priority

Name

kernel background priority - specifies the priority of the processing of batches of operating system

updates in relationship to the flash update processing

Syntax

kernel background priority [lower | higher | flash]

no kernel background priority [lower | higher | flash]?

Mode

Global Configuration

Parameters

lower - flash updates are processed first

higher - operating system updates are processed first

flash - operating system updates are processed that the same priority as flash updates

kernel flash limit

Kernel Interface Page 48

Description

Because only interface routes are normally installed during a flash update, the remaining routes are

processed in batches in the background, when no routing protocol traffic is being received. The kernel

background priority command (along with the kernel background limit command) specifies how

these batches are processed.

The kernel background priority command specifies the priority of the processing of batches of

operating system updates in relationship to the flash update processing. The negative form of this

command, no kernel background priority, removes the configured priority value, and returns this to

its default value of lower. Note: Specifying a priority value in the no form of this command has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If kernel background priority is not specified, it is the same as if the user had specified the following:

(config)# kernel background priority lower

Command History

NGC 2.2 - This command was introduced.

Examples

The following example sets the background priority to flash, thereby giving operational system updates the same priority as flash updates.

(config)# kernel background priority flash

kernel flash limit

Name

kernel flash limit - specifies the number of routes processed during a flash update

Syntax

kernel flash limit [ number | none ]

no kernel flash limit [ number | none ]?

Mode

Global Configuration

Parameters

number | none - specifies the maximum number of routes that can be processed during a flash update or

specify that an unlimited number are processed. The valid value range for number is from 0 to

4,294,967,294, inclusive.

Description

A flash update results from protocol activity. The kernel flash limit command controls the number of

routes installed during a flash update, suspending the current protocol module until the flash completes. Typically, only up to twenty interface routes are normally installed during a flash update. The remaining routes are processed in batches in the background, when no routing protocol traffic is being processed.

The negative of this command, no kernel flash, reverts back to the default of maximum of 20 routes of

type interface. Note: Specifying a limit value in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

kernel flash type

Kernel Interface Page 49

Default

If kernel flash limit is not specified, it is the same as if the user had specified the following

(config)# kernel flash limit 20

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, the router is configured to flash up to 40 routes at a time.

(config)# kernel flash limit 40

kernel flash type

Name

kernel flash type - specifies the type of routes that will be processed during a flash update

Syntax

kernel flash type [ interface | interior | all ]

no kernel flash type [ interface | interior | all ]?

Mode

Global Configuration

Parameters

interface - specifies routes defined by an interface

interior - specifies routes within the domain

all - specifies all routes

Description

When routes change as a result of operating system or protocol module activity, the process of notifying the

Advanced Routing Suite protocol module is known as a "flash update." The kernel flash type command

specifies the type of routes that will be processed during a flash update. The operating system’s forwarding table interface is the first to be notified. The flash process is concerned with the following three types of routes:

interface routes - routes defined by an interface

interior routes - routes within the domain

all routes - routes defined within the domain and routes defined by an interface

The negative form of this command, no kernel flash type, resets the flash type to interface. Note:

Specifying a type value in the no form of this command has no effect on the configuration. Thus, it is

displayed above as optional.

Default

If kernel flash type is not specified, it is the same as if the user had specified the following:

(config)# kernel flash type interface

Command History

NGC 2.2 - This command was introduced.

kernel no-change

Kernel Interface Page 50

Examples

The following example specifies to process all routes during a flash update.

(config)# kernel flash type all

kernel no-change

Name

kernel no-change - determines whether change operations will be performed

Syntax

kernel no-change

no kernel no-change

Mode

Global Configuration

Parameters

none

Description

On systems supporting the routing socket, the kernel no-change command determines whether change

operations will be performed. If the command is configured, then change operations will not be performed,

only deletes and adds will. The negative of this command, no kernel no-change, reverts back to the

default of change operations being performed.

Default

By default, kernel no-change is disabled.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns kernel no-change on.

(config)# kernel no-change

kernel no-flush-at-exit

Name

kernel no-flush-at-exit - determines whether deletions occur during shutdown

Syntax

kernel no-flush-at-exit

no kernel no-flush-at-exit

Mode

Global Configuration

kernel no-install

Kernel Interface Page 51

Parameters

none

Description

During a Advanced Routing Suite shutdown/restart sequence, it may be desirable to keep the routes that existed at the time of the Advanced Routing Suite shutdown in the operating system’s forwarding table. This enables the router to continue forwarding packets while Advanced Routing Suite is being restarted. After a restart, the protocol modules are given a short amount of time (currently three minutes) to determine their routes. After three minutes, all residual routes not re-established by the protocol modules are flushed.

The following are four conditions under which Advanced Routing Suite does not flush a route:

The route is an interface route.

The route is a static route configured within a static retain command.

The kernel no-flush-at-exit command is configured.

The route’s static bit is set.

The kernel no-flush-at-exit command is handy on systems with thousands of routes. Upon startup,

Advanced Routing Suite will notice which routes are in the operating system’s forwarding table and not add them back.

The negative of this command, no kernel no-flush-at-exit, reverts back to the default of disabled.

Default

By default, kernel no-flush-at-exit is disabled.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns kernel no-flush-at-exit on.

(config)# kernel no-flush-at-exit

See Also

Chapter 8 Static Routes

kernel no-install

Name

kernel no-install - specifies to no install routes in the kernel Forwarding Information Base (FIB)

Syntax

kernel no-install

no kernel no-install

Mode

Global Configuration

Parameters

none

kernel remnant-holdtime

Kernel Interface Page 52

Description

The kernel no-install command specifies to not install routes in the kernel FIB. Normally, the route

with the lowest preference is installed in the kernel fowarding table and is the route exported to other protocols. When this command is configured, the associated static route will not be installed in the forwarding table when it is active, but it will still be eligible to be exported to other protocols.

The negative of this command, no kernel no-install, reverts back to the default of disabled.

Default

By default, kernel no-install is disabled.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns kernel no-install on.

(config)# kernel no-install

kernel remnant-holdtime

Name

kernel remnant-holdtime - sets the holdtime for remnant routes

Syntax

kernel remnant-holdtime time-seconds

no kernel remnant-holdtime time-seconds?

Mode

Global Configuration

Parameters

time-seconds - an integer between 0 and 900, inclusive

Description

When Advanced Routing Suite starts up, it reads the kernel forwarding table and installs corresponding routes into Advanced Routing Suite’s routing table. These routes, with the exclusion of interface routes and routes configured via the UNIX route command, are called "remnants." Remnant routes are timed out after the specified interval, or as soon as a more attractive route is learned. This method allows forwarding to occur while the routing protocols start learning routes.

The negative of this command, no kernel remnant-holdtime, reverts back to the default of 180

seconds. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus,

it is displayed above as optional.

Default

If kernel-remnant holdtime is not specified, it is the same as if the user had specified the following:

(config)# kernel remnant-holdtime 180

Command History

NGC 2.2 - This command was introduced.

kernel routes

Kernel Interface Page 53

Examples

The following example changes the remnant-holdtime to 90 seconds.

(config)# kernel remnant-holdtime 90

kernel routes

Name

kernel routes - limits the maximum number of routes Advanced Routing Suite will install in the kernel

Syntax

kernel routes limit

no kernel routes limit?

Mode

Global Configuration

Parameters

limit - an integer in the range of 0 to 4,294,967,295, inclusive, on 32-bit systems and 0 to 264-1, inclusive,

on 64-bit systems

Description

On some systems, kernel memory is at a premium. With the kernel routes command, a limit can be

placed on the maximum number of routes Advanced Routing Suite will install in the kernel. This discussion is concerned with three types of routes:

interface routes - routes defined by an interface configuration (includes UNIX 'ifconfig' and 'route'

generated routes)

interior routes - routes within the domain

exterior routes - routes exterior to the domain

Normally, Advanced Routing Suite adds, changes, or deletes routes in interface/interior/exterior order. That is, Advanced Routing Suite queues interface routes first, followed by interior routes, followed by exterior routes, and then processes the queue from the beginning. When the route limit is reached, Advanced Routing Suite must ensure that interface/interior/exterior route preferences are followed. This is accomplished by first deleting kernel-based routes and then turning queued changes into adds. Finally, the list of active routes in the RIB is processed in interface/internal/external order, until the route limit is reached.

The negative of this command, no kernel routes, reverts back to the default of 232-1 (4,294,967,295)

routes for 32-bit systems and 264-1 routes for 64-bit systems. Note: Specifying a value for num in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

For 32-bit systems, if kernel routes is not specified, it is the same as if the user had specified the

following:

(config)# kernel routes 4294967295

For 64-bit systems, if kernel routes is not specified, it is the same as if the user had specified the

following:

(config)# kernel routes 18446744073709551616

Command History

NGC 2.2 - This command was introduced.

kernel trace file

Kernel Interface Page 54

Examples

The following example limits the number of routes to 500.

(config)# kernel routes 500

kernel trace file

Name

kernel trace file - specifies file options when tracing in the kernel interface

Syntax

kernel trace file file_name [no-timestamp || overwrite]?

no kernel trace file file_name [ no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. The kernel trace file command specifies a file for tracing of all

Kernel events. The negative form of this command disables this tracing. The specific events that are traced

are controlled The no-timestamp option disables the pre-pending of a timestamp to all lines written to the

trace file. The default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config)# kernel trace file /var/log/kernel.log no-timestamp

(config)# kernel trace file /var/log/kernel.log max-files 10

The option given in the second command completely replaces that given in the first. In order to specify both

no-timestamp and max-files 10, they must be entered on the same line as follows.

(config)# kernel trace file /var/log/kernel.log max-files 10 no-timestamp

Default

Kernel tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, kernel tracing is written to the file "/var/tmp/kernel.log". No timestamp will display at the beginning of the trace lines.

(config)# kernel trace file /var/tmp/kernel.log no-timestamp

kernel trace flag

Kernel Interface Page 55

kernel trace flag

Name

kernel trace flag - specifies Kernel-specific tracing options as well as options that are common across

all protocols

Syntax

kernel trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ symbol | remnants | interface-list | request | info ] ) | ( [ packets | redirect | other | routes | interface ] [ send | receive | send-receive ]? [detail?] )

no kernel trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ symbol | remnants | interface-list | request | info ] ) | ( [ packets | redirect | other | routes | interface ] [ send | receive | send-receive ]? [detail?] )

Mode

Global Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

Kernel-specific flags that do not allow send, receive, send-receive, or detail actions:

[ symbol | remnants | interface-list | request | info ] - These Kernel-specific flags cannot

be associated with the send, receive, or send-receive action items. These flags are defined as follows:

symbol - specifies to trace symbols, which are read from the kernel. The only useful way to specify this

level of tracing is via the Advanced Routing Suite -t option, because the symbols are read from the

kernel before parsing the configuration file.

remnants - specifies to trace remnants, or routes read from the kernel when Advanced Routing Suite

starts

interface-list - specifies to trace the interface list. interface-list is useful whenspecified with

the Advanced Routing Suite -t option because the first interface list scan is performed before any

configuration information is processed.

request - specifies to trace requests that specify to add, delete, or change routes in the kernel

forwarding table

show kernel

Kernel Interface Page 56

info - specifies to trace info messages, which are messages received from the routing socket, such as

TCP lossage, routing lookup failure, and route resolution requests. Advanced Routing Suite does not currently process these messages, but logs the information if requested.

Kernel-specific flags that allow associated actions:

[ packets | redirect | other | routes | interface ] - These Kernel-specific flags can be

associated with the send, receive, or send-receive action items. These flags are defined as follows:

packets - specifies to trace all kernel packet types

redirect - specifies to trace redirect messages, which are received from the kernel

other - specifies to trace other messages that are received from the kernel, including those mentioned

in the info type above. This option is currently not being used and is reserved for future use.

routes - specifies to trace routes that are exchanged with the kernel, including add, delete, or change

messages and add, delete, or change messages received from other processes

interface - specifies to trace interface status messages that are received from the kernel. These are

supported only on systems with networking code derived from BSD 4.4.

[send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the kernel trace flag command to specify tracing flags for Kernel tracing. Each flag must reside on

its own configuration line. For example, you cannot specify to trace both symbol and remnant packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received redirect and interface messages are traced in detail. This tracing information will be written to the file /var/tmp/kernel.log.

(config)# kernel trace file /var/tmp/kernel.log

(config)# kernel trace flag redirect send-receive detail

(config)# kernel trace flag interface send-receive detail

show kernel

Name

show kernel - displays information about kernel settings and support

Syntax

show kernel

Mode

User Execution

show kernel

Kernel Interface Page 57

Parameters

none

Description

The show kernel query displays information about kernel settings and support.

These fields have the following meanings.

no-change - If this setting is set to "on" for systems supporting the routing socket, then change operations

will not be performed. Only deletes and adds will be performed. This is useful on early versions of the

routing socket code where the change operation was broken. This option can be toggled with the kernel

no-change command.

no-flush-at-exit - During normal shutdown processing, Advanced Routing Suite deletes from the

kernel forwarding table all routes that the kernel does not flag as "retain". Setting this option to "on" prevents

route deletions at shutdown. During a Advanced Routing Suite shutdown/restart sequence, it may be desirable to keep in the kernel forwarding table the routes that existed at the time of the Advanced Routing Suite shutdown. This allows the router to continue forwarding packets while Advanced Routing Suite is being restarted.

After a restart, the protocol modules are given a short amount of time (currently three minutes) to determine their routes. After three minutes, all residual routes not re-established by the protocol modules are flushed.

There are four conditions under which Advanced Routing Suite does not flush a route:

Interface routes

Static routes with "retain" specified

Routes specified with "noflushexit"

Routes with static bit set

The no-flush-at-exit option is convenient on systems with thousands of routes. Upon startup,

Advanced Routing Suite will notice the routes that are in the kernel's forwarding table and not add them back.

This option can be toggled with the kernel no-flush-at-exit command.

reject support - This value indicates whether the operating system supports reject routes.

blackhole support- This value indicates whether the operating system supports blackhole routes.

variable length subnet support - This value indicates whether the operating system supports data

forwarding using variable length subnet masks.

host route support - This value indicates whether the operating system supports hosts routes.

multipath support - This value indicates whether the operating system supports multipath routing.

IPv4 forwarding enabled - This value indicates whether IPv4 forwarding is turned on in the operating

system.

UDP checksums enabled - This value indicates whether UDP checksums are turned on in the operating

system.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays a response for the show kernel query.

> show kernel

no-change: on no-flush-at-exit: off reject support: yes blackhole support: yes variable length subnet support: no host route support: yes multipath support: yes IPv4 forwarding enabled: yes IPv6 forwarding enabled: no UDP checksums enabled: no

show kernel

Kernel Interface Page 58

Page 59

Chapter 5

Martian Addresses

In This Chapter

Martian Addresses Overview 59

martian 59

Martian Addresses Overview Martians are networks that are considered illegal to be routed on the Internet. The martian command

allows additions to the list of martian addresses. An accept option can also be specified to explicitly allow a

subset of a range that was disallowed. The martian command can also be used for route filtering. Any

prefixes that are declared to be martians will be automatically filtered out from all received and advertised routes. However routes already in the routing table will not be removed if declared as martian until the next neighbor or protocol reset (for example, a BGP neighbor soft reconfig).

RFC 1918 specifies these networks as part of the private Internet space:

10.0.0.0 - 10.255.255.255 (10/8 prefix)

172.16 - 172.31.255.255 (172.16/12 prefix)

192.168.0.0 - 192.168.255.255 (192.168/16 prefix)

The prefixes are considered un-routable between autonomous systems. However, these prefixes can be routed within autonomous systems. Advanced Routing Suite does not treat these as martian addresses, but

the martian command will allow you to treat private address space as illegal for routing within an

autonomous system. RFC 1700 specifies common usage for IP numbers.

The default list of martians is:

127/8 (127.0.0.0 netmask 255.0.0.0) - 127.x.x.x is specified by RFC 1700 to loop back addresses. RFC 1700 (page 4, item g) states "these addresses should never appear outside a host". Address 127.0.0.1 is normally used as a loopback address.

224/3 - these are the multicast addresses.

martian

Name

martian - configures a martian address

Syntax

martian ipv4-addr ipv4-address [ mask mask | masklen masklen ] [ accept | reject ] [ (ge length) || (le length) ]?

no martian ipv4-addr ipv4-address [ mask mask | masklen masklen ] [ accept | reject ] [ (ge length) || (le length) ]?

martian

Martian Addresses Page 60

Mode

Global Configuration

Parameters

IPv4

ipv4-addr ipv4-address - specify ipv4-addr with an address in dotted-quad format that, when

combined with mask or masklen, specifies a set of martian addresses

mask mask | masklen masklen - specify either an integer mask length (from 0 to 32, inclusive) or specify

a contiguous mask in dotted-quad format

accept | reject - specify whether the prefix should be allowed to be routed or should be rejected

ge length - optionally specify that the configured martian matches prefix and mask pairs with exactly the

same prefix address and with mask lengths that are greater than or equal to this value. The value range for length is 0 to 32, inclusive. Additionally, it must be at least the value of masklen (or the number of significant

bits in mask) and no greater than the value of le.

le length - optionally specify that the configured martian matches prefix and mask pairs with exactly the

same prefix address and with mask lengths that are less than or equal to this value. The value range for length is 0 to 32, inclusive. Additionally, it must be at least the value of masklen (or the number of significant

bits in mask) and no less than the value of ge.

Description

Use the martian command to configure one or more martian addresses. Martians are networks that are

considered illegal to be routed on the Internet. This command allows you to specify private Internet space as

un-routable. Conversely, you can use the accept option to explicitly allow a subset of a range that was

disallowed.

If neither ge nor le is specified, then ge and le default to the configured masklen (or to the IPv4 contiguous

mask value).

If ge is specified, but le is not, then le defaults to the maximum mask length for the address family.

If le is specified but ge is not, then ge defaults to masklen.

Note: Order is not important when specifying ranges. For example, you may want to configure a range to be unroutable, then configure a more specific range within that range to be routable. The lookup always finds the most specific entry (the match with the longest prefix) regardless of the order in which the entries were entered.

Default

The default list of martians include:

127/8 - specified by RFC 1700 to loop back addresses. RFC 1700 (page 4, item g) states "these

addresses should never appear outside a host." Address 127.0.0.1 is normally used as a loopback address.

224/3 - the multicast addresses

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures 35/8 as a martian prefix.

(config)# martian ipv4-addr 35.0.0.0 masklen 8 reject

martian

Martian Addresses Page 61

Example 2

In this example, the IPv4 address 127.168.14.15, which would normally be considered a martian route per RFC 1918, is removed from the martian list.

(config)# martian ipv4-addr 127.168.14.15 masklen 32 accept

Example 3

The following example configures the IPv4 addresses within 32.0.0.0, with a mask-length of 8 and a prefix length of at least 16, as martian addresses.

(config)# martian ipv4-addr 32.0.0.0 masklen 8 reject ge 16

Page 62

Chapter 6

Multicast

In This Chapter

Multicast Overview 62

clear ip mroute 62

ip multicast boundary 63

ip multicast ttl-threshold 63

show ip mroute 64

show ip multicast boundary 65

show ip multicast ttl-threshold 66

Multicast Overview The multicast commands are used to set interface-specific options such as time-to-live (TTL) thresholds and administratively scoped boundaries.

clear ip mroute

Name

clear ip mroute - clears routes in the multicast routing table

Syntax

clear ip mroute gr_address? sr_address?

Mode

User Execution

Parameters

gr_address - optionally specify a valid IPv4 multicast group address that you want removed from the multicast routing table

sr_address - optionally specify a valid IPv4 multicast source address that you want removed from the multicast routing table

Description

Use the clear ip mroute command to remove routes from the multicast routing table. If this command is

issued without arguments, then all group and source information will be cleared. Similarly, you can specify to clear a specific group and/or source multicast address.

Command History

NGC 2.2 - This command was introduced.

ip multicast boundary

Multicast Page 63

Examples

The following example clears group/source 226.1.1.1/192.168.0.1 from the multicast routing table.

> clear ip mroute 226.1.1.1 192.168.0.1

ip multicast boundary

Name

ip multicast boundary - specifies an administratively scoped boundary for a single multicast group on

the associated interfaces.

Syntax

ip multicast boundary group group-address masklen length

no ip multicast boundary group group-address masklen length

Mode

Interface Configuration

Parameters

group group-address - specify a valid IPv4 address to denote the group address

masklen length - the length of the mask associated with the group prefix, specified as an integer

Description

ip multicast boundary is used to configure administratively scoped group boundaries on the indicated

interface(s).

Default

The ip multicast boundary command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, an administratively scoped boundary for multicast group 224.5.5.5 is configured.

(config-if)# ip multicast boundary group 224.5.5.5 masklen 24

ip multicast ttl-threshold

Name

ip multicast ttl-threshold - specifies the minimum time-to-live that a multicast data packet can

have and still be forwarded over the associated interface

Syntax

ip multicast ttl-threshold ttl

no ip multicast ttl-threshold [ ttl ]?

show ip mroute

Multicast Page 64

Mode

Interface Configuration

Parameters

ttl - an integer from 0 to 255, inclusive

Description

The ip multicast ttl-threshold command specifies the minimum time-to-live plus1 that a multicast

data packet can have and still be forwarded over the associated interface. A value of 0 indicates that no multicast data packets should be forwarded over the associated interface(s).

Default

If ip multicast ttl-threshold is not configured, it is the same as if the user had specified the

following: (config-if)# ip multicast ttl-threshold 0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a threshold of 20 on interface fxp1.

(config)# interface fxp1

(config-if)# ip multicast ttl-threshold 20

show ip mroute

Name

show ip mroute - displays the contents of the Multicast Routing Table

Syntax

show ip mroute

Mode

User Execution

Parameters

none

Description

The output of the show ip mroute query displays the content of the Multicast routing table.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows a response to the show ip mroute query.

> show ip mroute

IP Multicasting Routing Table

show ip multicast boundary

Multicast Page 65

(*, 224.1.1.1), uptime 0:01:20 Incoming interface: fxp0, RPF neighbor 10.2.11.31 Outgoing interface list: fxp1

(192.168.101.100, 224.2.2.2), uptime 0:01:20 Incoming interface: fxp1, RPF neighbor 10.2.12.32 Outgoing interface list: fxp1

Field Descriptions

The following table describes the fields that appear in the Multicast MRT Query.

Table 11-1 Multicast MRT Query Fields

Field Description

(*, 224.1.1.1), (192.168.101.100, 224.2.2.2)

The entries in the IP multicast routing table.

Uptime The length of time that the (*,G) or (S,G) entry has been created in hours:minutes:seconds.

Incoming interface The expected interface for a multicast packet from the source.

RPF neighbor The IP address of the upstream router to the source.

Outgoing interface list The interfaces through which packets will be forwarded.

show ip multicast boundary

Name

show ip multicast boundary - displays all boundaries within all interfaces

Syntax

show ip multicast boundary

Mode

User Execution

Parameters

none

Description

Use the show ip multicast boundary query to obtain summarized information for all boundaries within

all interfaces.

show ip multicast ttl-threshold

Multicast Page 66

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows a response to the show ip multicast boundary query.

> show ip multicast boundary

[1]fxp0, 224.5.5.0/24

[2]fxp0, 224.5.10.0/24

[3]fxp1, 239.5.0.0/16

show ip multicast ttl-threshold

Name

show ip multicast ttl-threshold - displays information about the multicast TTL threshold

Syntax

show ip multicast ttl-threshold

Mode

User Execution

Parameters

none

Description

The output of the show ip multicast ttl-threshold query displays information about the multicast

TTL threshold.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows the output of a show ip multicast ttl-threshold query.

> show ip multicast ttl-threshold fxp0, 1 fxp2, 5

Field Descriptions

The following table describes the fields that appear in the Multicast TTL Threshold Query.

Table 11-1 Multicast TTL Threshold Query Fields

Field Description

fxp0, 1 and fxp1, 5 Shows the ttl-threshold value for each interface.

Page 67

Chapter 7

Trace Options

In This Chapter

Trace Options Overview 67

trace file 67

trace flag 68

Trace Options Overview The trace command controls Advanced Routing Suite’s tracing options. These options can be configured

at many levels. Tracing options include the file specifications and global and protocol-specific tracing options. Unless overridden, tracing options from the next higher level are inherited by lower levels. For example, BGP peer tracing options are inherited from BGP group tracing options, which are inherited from global BGP tracing options, which are inherited from global Advanced Routing Suite tracing options. At each level, additional tracing specifications override the inherited options.

Global tracing configurations have an immediate effect. Tracing values inherited by protocols specified in a configuration are initially inherited from the global options that are currently in effect as the protocol configuration entries are entered, unless they are overridden by more specific options.

The file options in subsequent trace configurations with the same file name modify the previously set

values for the files.

trace file

Name

trace file - specifies the file to receive tracing information, the size of the file, whether to overwrite

existing files, and the maximum number of files allowed

Syntax

trace file file_name [no-timestamp || overwrite]?

no trace file file_name [no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

trace flag

Trace Options Page 68

Description

This command specifies a file for tracing of all protocols. The negative form of this command disables this

tracing. The specific events that are traced are controlled by the trace flag command. The trace file

command is also associated with each protocol, so that information pertaining to a single protocol can be written to its own file.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands.

Default

Global tracing options are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, tracing is written to the file "gated.log". No timestamp will display at the beginning of the trace lines.

(config)# trace file gated.log no-timestamp

trace flag

Name

trace flag - specifies global tracing options that are common across all protocols

Syntax

trace flag ( [ route | normal | state | policy | task | timer | all ] )

no trace flag ( [ route | normal | state | policy | task | timer | all ] )

Mode

Global Configuration

Parameters

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

trace flag

Trace Options Page 69

Description

Use the trace flag command to specify global tracing flags. Each flag must reside on its own

configuration line. For example, you cannot specify to trace both task and policy packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, flags specify to trace both timer usage and state machine transition. This tracing information will be written to the file gated.log.

(config)# trace file gated.log

(config)# trace flag timer

(config)# trace flag state

Page 70

Chapter 8

Border Gateway Protocol (BGP)

In This Chapter

Border Gateway Protocol (BGP) Overview 72

address-family 76

bgp always-compare-med 77

bgp as-path-loops 77

bgp bestpath as-path ignore 78

bgp bestpath compare-cluster-list-length 79

bgp bestpath compare-originator-id 80

bgp bestpath compare-router-id 80

bgp bestpath med confed 81

bgp bestpath med missing-as-worst 82

bgp cluster-id 83

bgp confederation identifier 84

bgp confederation peers 84

bgp non-leading-confeds 85

bgp open-on-accept 86

bgp pass-optional-nontrans 87

bgp restart-defer 88

bgp restart-delete-remnants 89

bgp restart-time 89

bgp restart-timeout 90

bgp router-id 91

bgp send-group-always 92

bgp tie-break-on-age 92

clear ip bgp 93

default-metric 94

distance 95

distribute-list 96

enable 97

maximum-routes 98

neighbor add-communities 99

neighbor aggregator-id 99

neighbor allow 101

neighbor as-loop 102

neighbor as-override 103

neighbor aspath-prepend 103

neighbor capability orf comm-filter 104

neighbor capability orf extcomm-filter 105

neighbor capability orf prefix-filter 106

neighbor cluster-id 107

neighbor distance 108

neighbor dynamic 109

trace flag

Border Gateway Protocol (BGP) Page 71

neighbor enable 110

neighbor end-of-rib 110

neighbor export-localpref 111

neighbor graceful-restart 112

neighbor ignore-leading-as 113

neighbor import-localpref 114

neighbor keep 115

neighbor keepalives-always 116

neighbor local-as 117

neighbor log-up-down 118

neighbor maximum-routes 119

neighbor metric-out 120

neighbor multi-protocol-nexthop 121

neighbor next-hop-self 122

neighbor orf comm-list 123

neighbor orf extcomm-list 124

neighbor orf prefix-list 125

neighbor out-delay 126

neighbor passive 126

neighbor password 127

neighbor pedantic 128

neighbor peer-group 129

neighbor preference2 130

neighbor receive-buffer 131

neighbor remote-as 132

neighbor remove-private-as 133

neighbor route-map 134

neighbor route-reflector-client 135

neighbor route-to-peer 136

neighbor send-buffer 137

neighbor send-community 137

neighbor soft-reconfiguration inbound 138

neighbor timers 139

neighbor ttl 140

neighbor update-source 141

neighbor use-med 142

neighbor v4-gateway 143

neighbor version 144

network 145

preference2 146

redistribute 147

router bgp 149

show ip bgp 149

show ip bgp instance 150

show ip bgp neighbors 151

show ip bgp orf 152

show ip bgp paths 153

show ip bgp peer-group 154

show ip bgp summary 155

timers bgp 155

trace file 157

Border Gateway Protocol (BGP) Overview

Border Gateway Protocol (BGP) Page 72

trace flag 158

Border Gateway Protocol (BGP) Overview The Border Gateway Protocol (BGP) is an exterior, or inter-domain, routing protocol. BGP is used to exchange routing information between multiple transit autonomous systems, between transit and stub autonomous systems, or between two stub autonomous systems.

BGP uses path attributes to provide more information about each route and in particular to maintain an autonomous system (AS) path. An AS path includes the AS number of each autonomous system that the route has transited, which provides information sufficient to prevent routing loops in an arbitrary topology. Path attributes can also be used to distinguish between groups of routes to determine administrative preferences, allowing greater flexibility in determining route preference to achieve a variety of administrative ends. Advanced Routing Suite supports version 4 of the BGP protocol.

BGP supports two basic types of sessions between neighbors: internal (sometimes referred to as IBGP) and external (EBGP). Internal sessions are run between routers in the same autonomous system. External sessions run between routers in different autonomous systems. When a router routes to an external peer, the local AS number is prepended to the AS path. This means that routes received from an external peer are guaranteed to have the AS number of that peer at the start of the path. In general, routes received from an internal neighbor will not have the local AS number prepended to the AS path. Those routes will have the same AS path that the route had when the first internal neighbor received the route from an external peer. Routes with no AS numbers in the path may be legitimately received from internal neighbors. These routes should be considered internal to the receiver's own AS.

External BGP sessions may or may not include a single metric, which BGP calls the Multi-Exit Discriminator (MED) among the path attributes. MED is a 32-bit unsigned integer. Smaller values of the MED are preferred. This metric is used only to break ties between routes with equal preference from the same neighboring AS.

Internal BGP sessions carry at least one metric in the path attributes, which BGP calls the Local_Pref. A

route is preferred if its value for this metric is larger. Internal sessions can optionally include a second metric, the MED, carried in from external sessions.

BGP collapses as many routes with similar path attributes as it can into a single update for advertisement. The churn caused by the loss of a neighbor will be minimized, and the initial advertisement sent during peer establishment will be maximally compressed. BGP does not read information from the kernel message by message, but fills the input buffer. BGP processes all complete messages in the buffer before reading again. BGP also does multiple reads to clear all incoming data queued on the socket. This feature may cause other protocols to be blocked for prolonged intervals by a busy peer connection. All unreachable messages are collected into a single message and sent prior to reachable routes during a flash update. Another update is sent once the maximum packet size is reached.

Advanced Routing Suite will determine the immediate next hop to use for a next hop sent in a BGP update by finding the best matching (most specific) route in the routing table that covers the address of the BGP next hop. This allows BGP to support distant BGP peers that might not be directly connected.

BGP allows unconfigured peers to connect if an appropriate group has been configured with a "neighbor allow" ("neighbor allow" on page 101) command.

Notes:

1. The peer-group command is used to create peer groups that share common attributes.

2. Within the peer-group command, the neighbor commands are used to individually specify peers and

to permit overriding specific peering group options.

3. When comparing routes with the same MEDs, BGP first prefers routes learned from external routers (EBGP), followed by confederation external routers, over routes learned from internal routers (IBGP).

BGP Decision Process

BGP uses the following decision process when selecting between multiple routes to the same destination:

1. Prefer the route with the lowest Advanced Routing Suite preference.

2. Prefer the route with the lowest Advanced Routing Suite preference2.

3. Prefer the route with the highest LOCAL_PREF value.

Border Gateway Protocol (BGP) Overview

Border Gateway Protocol (BGP) Page 73

4. Prefer the route with the shortest path, excluding confederation segments.

5. Prefer the route with the "best" ORIGIN: IGP is better than EGP which is better than incomplete.

6. If "bgp always-compare-med" ("bgp always-compare-med" on page 77) has not been configured, prefer any routes that do not have an inferior MED. Routes are considered to have an inferior MED if two routes to the same destination have been learned with the same neighbor AS, and one of the routes being considered does not have the lowest MED received for routes to that destination from the same neighbor AS. If confed-MED is specified, neighbor AS is considered to be the first AS in the AS_PATH, or the local AS if there are no AS numbers in the AS_PATH. If confed-MED is not specified, neighbor AS is considered to be the first AS in the first non-confed segment of the AS_PATH, or the local confederation-id if there are no AS numbers in a non-confed segment of the AS_PATH. If "bgp always-compare-med" ("bgp always-compare-med" on page 77) has been configured, prefer the route with the lowest MED.

7. Prefer the route with the lowest IGP cost to the BGP nexthop. IGP cost is determined by comparing the preference, then the preference 2, then the metric, and finally the metric 2 of the two resolving routes.

8. Prefer routes received from external peers.

9. If "bgp tie-break-on-age" ("bgp tie-break-on-age" on page 92) has been specified, prefer the older route.

10. If "bgp bestpath compare-router-id" ("bgp bestpath compare-router-id" on page 80) has been specified, prefer the route learned with the lowest router ID. The router ID is taken from the Open message of the peering session over which the route was received, unless "bgp bestpath compare-originator-id" ("bgp bestpath compare-originator-id" on page 80) has been specified, and the route was received with an ORIGIN_ID. In the latter case, the ORIGIN_ID is used instead of the router ID from the Open message.

11. If "bgp bestpath compare-cluster-list-length" ("bgp bestpath compare-cluster-list-length" on page 79) has been specified, prefer the route with the lowest CLUSTER_LIST length.

12. Prefer the route with the lowest neighbor address.

Dynamic Capabilities

BGP Dynamic Capabilities allow the communication of a change in a BGP peer’s capabilities without having to restart the peering session.

The BGP implementation is done on a per-peer basis and in such a way that dynamic capabilities are supported as long as the BGP peer supports BGP Dynamic Capabilities. Advanced Routing Suite's BGP advertises Dynamic Capabilities in the OPEN message. If a BGP peer advertises support for BGP Dynamic Capabilities in the OPEN message, then Advanced Routing Suite turns on Dynamic Capabilities. Otherwise, the dynamic capabilities for this peer will be disabled.

The Advanced Routing Suite BGP supports the following BGP Dynamic Capabilities:

Multi-protocol Capabilities

Graceful Restart

Route Refresh

BGP Commands

Global Configuration Mode BGP Commands

"router bgp" ("router bgp" on page 149)

Global BGP Commands

"address-family" ("address-family" on page 76)

"bgp always-compare-med" ("bgp always-compare-med" on page 77)

"bgp as-path-loops" ("bgp as-path-loops" on page 77)

"bgp bestpath as-path ignore" ("bgp bestpath as-path ignore" on page 78)

"bgp bestpath compare-cluster-list-length" ("bgp bestpath compare-cluster-list-length" on page 79)

"bgp bestpath compare-originator-id" ("bgp bestpath compare-originator-id" on page 80)

"bgp bestpath compare-router-id" ("bgp bestpath compare-router-id" on page 80)

"bgp bestpath med confed" ("bgp bestpath med confed" on page 81)

Border Gateway Protocol (BGP) Overview

Border Gateway Protocol (BGP) Page 74

"bgp bestpath med missing-as-worst" ("bgp bestpath med missing-as-worst" on page 82)

"bgp cluster-id" ("bgp cluster-id" on page 83)

"bgp confederation identifier" ("bgp confederation identifier" on page 84)

"bgp confederation peers" ("bgp confederation peers" on page 84)

"bgp non-leading-confeds" ("bgp non-leading-confeds" on page 85)

"bgp open-on-accept" ("bgp open-on-accept" on page 86)

"bgp pass-optional-nontrans" ("bgp pass-optional-nontrans" on page 87)

"bgp restart-defer" ("bgp restart-defer" on page 88)

"bgp restart-delete-remnants" ("bgp restart-delete-remnants" on page 89)

"bgp restart-time" ("bgp restart-time" on page 89)

"bgp restart-timeout" ("bgp restart-timeout" on page 90)

"bgp router-id" ("bgp router-id" on page 91)

"bgp send-group-always" ("bgp send-group-always" on page 92)

"bgp tie-break-on-age" ("bgp tie-break-on-age" on page 92)

"default-metric" ("default-metric" on page 94)

"distance" ("distance" on page 95)

"distribute-list" ("distribute-list" on page 96)

"enable" ("enable" on page 97)

"maximum-routes" ("maximum-routes" on page 98)

"network" ("network" on page 145)

"preference2" ("preference2" on page 146)

"redistribute" ("redistribute" on page 147)

"timers bgp"

"trace file"

"trace flag"

BGP Neighbor Commands

"neighbor add-communities" ("neighbor add-communities" on page 99)

"neighbor aggregator-id" ("neighbor aggregator-id" on page 99)

"neighbor allow" ("neighbor allow" on page 101)

"neighbor as-loop" ("neighbor as-loop" on page 102)

"neighbor as-override" ("neighbor as-override" on page 103)

"neighbor aspath-prepend" ("neighbor aspath-prepend" on page 103)

"neighbor capability orf comm-filter" ("neighbor capability orf comm-filter" on page 104)

"neighbor capability orf extcomm-filter" ("neighbor capability orf extcomm-filter" on page 105)

"neighbor capability orf prefix-filter" ("neighbor capability orf prefix-filter" on page 106)

"neighbor cluster-id" ("neighbor cluster-id" on page 107)

"neighbor distance" ("neighbor distance" on page 108)

"neighbor dynamic" ("neighbor dynamic" on page 109)

"neighbor enable" ("neighbor enable" on page 110)

"neighbor end-of-rib" ("neighbor end-of-rib" on page 110)

"neighbor export-localpref" ("neighbor export-localpref" on page 111)

"neighbor ignore-leading-as" ("neighbor ignore-leading-as" on page 113)

Border Gateway Protocol (BGP) Overview

Border Gateway Protocol (BGP) Page 75

"neighbor import-localpref" ("neighbor import-localpref" on page 114)

"neighbor keep" ("neighbor keep" on page 115)

"neighbor keepalives-always" ("neighbor keepalives-always" on page 116)

"neighbor local-as" ("neighbor local-as" on page 117)

"neighbor log-up-down" ("neighbor log-up-down" on page 118)

"neighbor maximum-routes" ("neighbor maximum-routes" on page 119)

"neighbor metric-out" ("neighbor metric-out" on page 120)

"neighbor multi-protocol-nexthop" ("neighbor multi-protocol-nexthop" on page 121)

"neighbor next-hop-self" ("neighbor next-hop-self" on page 122)

"neighbor orf comm-list" ("neighbor orf comm-list" on page 123)

"neighbor orf extcomm-list" ("neighbor orf extcomm-list" on page 124)

"neighbor orf prefix-list" ("neighbor orf prefix-list" on page 125)

"neighbor out-delay" ("neighbor out-delay" on page 126)

"neighbor passive" ("neighbor passive" on page 126)

"neighbor password" ("neighbor password" on page 127)

"neighbor pedantic" ("neighbor pedantic" on page 128)

"neighbor peer-group" ("neighbor peer-group" on page 129)

"neighbor preference2" ("neighbor preference2" on page 130)

"neighbor receive-buffer" ("neighbor receive-buffer" on page 131)

"neighbor remote-as" ("neighbor remote-as" on page 132)

"neighbor remove-private-as" ("neighbor remove-private-as" on page 133)

"neighbor route-map" ("neighbor route-map" on page 134)

"neighbor route-reflector-client" ("neighbor route-reflector-client" on page 135)

"neighbor route-to-peer" ("neighbor route-to-peer" on page 136)

"neighbor send-buffer" ("neighbor send-buffer" on page 137)

"neighbor send-community" ("neighbor send-community" on page 137)

"neighbor soft-reconfiguration inbound" ("neighbor soft-reconfiguration inbound" on page 138)

"neighbor timers" ("neighbor timers" on page 139)

"neighbor ttl" ("neighbor ttl" on page 140)

"neighbor update-source" ("neighbor update-source" on page 141)

"neighbor use-med" ("neighbor use-med" on page 142)

"neighbor v4-gateway" ("neighbor v4-gateway" on page 143)

"neighbor version" ("neighbor version" on page 144)

Querying and Clearing Commands

"clear ip bgp" ("clear ip bgp" on page 93)

"show ip bgp" ("show ip bgp" on page 149)

"show ip bgp instance"

"show ip bgp neighbors"

"show ip bgp orf"

"show ip bgp paths"

"show ip bgp peer-group"

"show ip bgp summary"

address-family

Border Gateway Protocol (BGP) Page 76

address-family

Name

address-family - configures multi-protocol support for BGP peers

Syntax

address-family [ipv4 (unicast | multicast | vpn)]

no address-family [ipv4 (unicast | multicast | vpn)]

Mode

BGP Router Configuration

Parameters

ipv4 - configures address family mode for either IPv4

unicast | multicast - configures address family mode for unicast

multicast - configures address family mode for either multicast

vpn - configures address family mode for VPN

Description

The address-family command is a mode within a BGP router configuration. It is used to configure

multi-protocol support for BGP peers.

Notes

The vpn keyword is only available if one of the following flags is used to build Advanced Routing Suite:

--enable-vri, --enable-vpn4, or

--enable-mpbgp_vpn4. See "Appendix A Build Flags" in Installing Advanced Routing Suite NGC 2.4

for more information.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example will enter address family mode for IPv4 multicast. Notice that the prompt changes to

(config-router-af)#.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# address-family ipv4 multicast

(config-router-af)# neighbor 1.2.3.4 activate

Example 2

The following example removes all address-family configuration for IPv4 multicast.

(config)# router bgp 64512

(config-router-bgp)# no address-family ipv4 multicast

(config-router-bgp)# exit

bgp always-compare-med

Border Gateway Protocol (BGP) Page 77

(config)#

bgp always-compare-med

Name

bgp always-compare-med - specifies whether to compare when routes with differing Multi-Exit

Discriminators (MEDs) are received from peers in different Autonomous Systems

Syntax

bgp always-compare-med

no bgp always-compare-med

Mode

BGP Router Configuration

Parameters

none

Description

When two routes to the same destination are received from peers in different Autonomous Systems, they

can have different MEDs. The bgp always-compare-med command allows you to specify whether to

compare those MEDs. When choosing between these routes, assuming that nothing else makes one preferable to the other (such as a configured policy), the values of the differing MEDs are used to choose the route to use. In this comparison, the route with the lowest MED is preferred. Routes without MEDs are treated as having the best possible MED.

Default

If bgp always-compare-med is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp always-compare-med

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables the comparison of MEDs among confederation paths.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp always-compare-med

(config-router-bgp)# exit

bgp as-path-loops

Name

bgp as-path-loops - specifies the number of times an autonomous system may appear in an AS path

Syntax

bgp as-path-loops loop-count

no bgp as-path-loops loop-count?

bgp bestpath as-path ignore

Border Gateway Protocol (BGP) Page 78

Mode

BGP Router Configuration

Parameters

loop-count - an integer in the range 1 to 10, inclusive

Description

The bgp as-path-loops command specifies the number of times this autonomous system can appear in

an AS path. loop-count is an integer in the range 1 to 10, inclusive. The negative form of this command, no

bgp as-path-loops, removes the configured loop-count value and returns this to its default value of 1.

Notes:

Specifying a value for loop-count in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

This command should not be used in normal operations.

Default

If bgp as-path-loops is not specified for an autonomous system setting, it is the same as if the user had

specified the following:

(config-router-bgp)# bgp as-path-loops 1

Command History

NGC 2.2 - This command was introduced.

Examples

In this example, the router's AS number is set to 7476 and the number of loops is set to 2.

(config)# router bgp 7476

(config-router-bgp)# bgp as-path-loops 2

(config-router-bgp)# exit

bgp bestpath as-path ignore

Name

bgp bestpath as-path ignore - specifies to ignore the AS_PATH length when breaking ties between

BGP routes

Syntax

bgp bestpath as-path ignore ignore

no bgp bestpath as-path ignore

Mode

BGP Router Configuration

Parameters

none

Description

Use bgp bestpath as-path ignore when you do not want the AS_PATH length to be considered when

breaking ties between BGP routes.

bgp bestpath compare-cluster-list-length

Border Gateway Protocol (BGP) Page 79

Default

If bgp bestpath as-path ignore is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp bestpath as-path ignore

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example Advanced Routing Suite will ignore the AS_PATH length when breaking ties

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp bestpath as-path ignore

(config-router-bgp)# exit

(config)

bgp bestpath compare-cluster-list-length

Name

bgp bestpath compare-cluster-list-length - enables breaking ties based on shortest cluster list

length

Syntax

bgp bestpath compare-cluster-list-length

no bgp bestpath compare-cluster-list-length

Mode

BGP Router Configuration

Parameters

none

Description

Use the bgp bestpath compare-cluster-list-length command to break ties between routes based

on shortest cluster list length.

Default

If bgp bestpath compare-cluster-list-length is not specified, it is the same as if the user had

specified the following:

(config-router-bgp)# no bgp bestpath compare-cluster-list-length

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example Advanced Routing Suite will consider cluster list length when breaking ties and use the route with the lowest length.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

bgp bestpath compare-originator-id

Border Gateway Protocol (BGP) Page 80

(config-router-bgp)# bgp bestpath compare-cluster-list-length

(config-router-bgp)# exit

(config)

bgp bestpath compare-originator-id

Name

bgp bestpath compare-originator-id - specifies to break ties based on lowest Originator ID value

Syntax

bgp bestpath compare-originator-id

no bgp bestpath compare-originator-id

Mode

BGP Router Configuration

Parameters

none

Description

Use the bgp bestpath compare-originator-id command to break ties between routes based the

Originator ID value instead of the neighbor’s router ID. When this command is configured, the route with the lowest Originator ID will be preferred over the router ID.

Default

If bgp bestpath compare-originator-id is not specified, it is the same as if the user had specified the

following:

(config-router-bgp)# no bgp bestpath compare-originator-id

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example Advanced Routing Suite will consider the Originator ID when breaking ties and use the route with the lowest Originator ID.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp bestpath compare-originator-id

(config-router-bgp)# exit

(config)

bgp bestpath compare-router-id

Name

bgp bestpath compare-router-id - specifies whether to ignore router IDs when breaking ties between

BGP routes

bgp bestpath med confed

Border Gateway Protocol (BGP) Page 81

Syntax

bgp bestpath compare-router-id

no bgp bestpath compare-router-id

Mode

BGP Router Configuration

Parameters

none

Description

By default, router IDs are considered when breaking ties with BGP routes. Use the no bgp bestpath

compare-router-id command when you do not want router IDs to be considered when breaking ties

between BGP routes.

Default

Router IDs are compared by default. Therefore, if bgp bestpath compare-router-id is not specified, it

is the same as if the user had specified the following:

(config-router-bgp)# bgp bestpath compare-router-id

Command History

NGC 2.2 - This command was introduced.

Examples

The following example cause Advanced Routing Suite to ignore router IDs when breaking ties between BGP routes.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# no bgp bestpath compare-router-id

(config-router-bgp)# exit

(config)#

bgp bestpath med confed

Name

bgp bestpath med confed - specifies that confederation segments within a route’s AS_PATH should not

be considered when determining the neighboring AS that a route was learned from, during MED comparison

Syntax

bgp bestpath med confed

no bgp bestpath med confed

Mode

BGP Router Configuration

Parameters

none

bgp bestpath med missing-as-worst

Border Gateway Protocol (BGP) Page 82

Description

When comparing MEDs, use bgp bestpath med confed to specify whether confederation segments

within a route’s AS_PATH should not be considered when determining the neighboring AS that a route was learned from.

Default

If bgp bestpath med confed is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp bestpath med confed

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables the comparison of MEDs among confederation paths.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp bestpath med confed

(config-router-bgp)# exit

(config)#

bgp bestpath med missing-as-worst

Name

bgp bestpath med missing-as-worst - specifies whether routes received without a MED are to be

considered when comparing BGP routes

Syntax

bgp bestpath med missing-as-worst

no bgp bestpath med missing-as-worst

Mode

BGP Router Configuration

Parameters

none

Description

When breaking ties between BGP routes, use the bgp bestpath med missing-as-worst command to

specify whether routes received without a MED are to be considered to have the worst legal MED.

Default

If bgp bestpath med missing-as-worst is not specified, it is the same as if the user had specified the

following:

(config-router-bgp)# no bgp bestpath med missing-as-worst

Command History

NGC 2.2 - This command was introduced.

bgp cluster-id

Border Gateway Protocol (BGP) Page 83

Examples

The following example cause Advanced Routing Suite to consider routes without a MED to have the worst legal MED.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp bestpath med missing-as-worst

(config-router-bgp)# exit

(config)#

bgp cluster-id

Name

bgp cluster-id - specifies the route reflection cluster ID for BGP

Syntax

bgp cluster-id router-id

no bgp cluster-id router-id

Mode

BGP Router Configuration

Parameters

router-id - a router ID in dotted-quad format used by route reflectors to prevent route propagation loops

within the cluster

Description

The bgp cluster-id command specifies the route reflection cluster ID for BGP. The cluster ID defaults to

be the same as the router ID. If a router is to be a route reflector, then a single cluster ID should be selected and configured on all route reflectors in the cluster. If there is only one route reflector in the cluster, the cluster-id setting can be omitted because the default will suffice.

The only constraints on the choice of cluster ID are the following:

IDs of clusters within an Autonomous System (AS) must be unique within that AS.

The cluster ID must not be 0.0.0.0

Default

The cluster ID value defaults to the router ID.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a cluster ID of 1.2.3.4 for AS 64512.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# bgp cluster-id 1.2.3.4

(config-router-bgp)# exit

(config)#

bgp confederation identifier

Border Gateway Protocol (BGP) Page 84

bgp confederation identifier

Name

bgp confederation identifier - configures the BGP router to be a member of a BGP confederation

Syntax

bgp confederation identifier confed_id

no bgp confederation identifier confed_id

Mode

BGP Router Configuration

Parameters

confed_id - an integer between 1 and 65535, inclusive

Description

A BGP router can be configured to be a member of a BGP confederation where the autonomous system is subdivided into several confederation AS’s. When configured as a confederation member, this router will represent itself as the configured AS number to confederation peers and as the configured confederation identifier to non-confederation peers.

Use the negative form of this command, no bgp confederation identifier, to remove the configured

confederation peer identifier.

Default

No BGP confederation identifiers are configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the BGP router to be a member of BGP confederation 65000.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp confederation identifier 65000

(config-router-bgp)# exit

(config)#

bgp confederation peers

Name

bgp confederation peers - configures a BGP group to be part of a BGP confederation

Syntax

bgp confederation peers as_number {1, n}

no bgp confederation peers as_number {1, n}

Mode

BGP Router Configuration

bgp non-leading-confeds

Border Gateway Protocol (BGP) Page 85

Parameters

as_number - an autonomous system number of a group of peers that should be designated as

confederation peers

{1, n} - When specified, the bgp confederation peers command must include at least one as_number

Description

The bgp confederation peers command configures a BGP group to be part of a BGP confederation.

When this command is present, Advanced Routing Suite will treat all members of that group as confederation peers.

Default

Confederation peers are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures peers in AS number 65535 and AS number 42 to be confederation peers.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp confederation peers 65535 42

(config-router-bgp)# exit

(config)#

bgp non-leading-confeds

Name

bgp non-leading-confeds - specifies the action to take when malformed AS_PATHs containing

non-prefixed confederation segments are received

Syntax

bgp non-leading-confeds [ notify | ignore | drop ]

no bgp non-leading-confeds [ notify | ignore | drop ]?

Mode

BGP Router Configuration

Parameters

notify - specifies that receipt of non-prefixed confederation segments will cause BGP to send a

notification message

ignore - specifies that routes containing non-prefixed confederation segments will be logged and ignored

drop - specifies that routes containing non-prefixed confederation segments will be logged and discarded

Description

"Buggy" routers on the Internet will sometimes illegally advertise AS_PATHs containing confederation segments outside of a confederation boundary. If these routes propagate beyond the confederation boundary edge, they will cause the peering session of any router that does not accept confederation segments from non-confederation peers to drop the peering session and thus disrupt service.

bgp open-on-accept

Border Gateway Protocol (BGP) Page 86

drop causes BGP to discard AS_PATHs that are received from BGP peers where there are BGP

Confederation AS_PATH segments (AS_CONFED_SEQUENCE, AS_CONFED_SET) occurring anywhere other than at the left-hand side of the AS_PATH.

ignore causes BGP to ignore AS_PATHs that are received from BGP peers where there are BGP

Confederation AS_PATH segments (AS_CONFED_SEQUENCE, AS_CONFED_SET) occurring anywhere other than at the left-hand side of the AS_PATH. This option will cause routes containing non-prefixed confederation segments to be logged and stored in the RIB with a preference or distance of -1.

notify causes BGP to send a notification upon receipt of BGP peers where there are BGP Confederation

AS_PATH segments (AS_CONFED_SEQUENCE, AS_CONFED_SET) occurring anywhere other than at the left-hand side of the AS_PATH.

The negative form of this command, no bgp non-leading-confeds, removes the user-defined

configuration and returns this to its default value of notify. Note: Specifying a parameter for this command

in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If bgp non-leading-confeds is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# bgp non-leading-confeds notify

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes Advanced Routing Suite to log and ignore non-prefixed confederation segments.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp non-leading-confeds ignore

(config-router-bgp)# exit

(config)#

Example 2

The following example removes the previously configured ignore command and returns this to its default value of notify.

(config)# router bgp 65535

(config-router-bgp)# no bgp non-leading-confeds

(config-router-bgp)# exit

(config)#

bgp open-on-accept

Name

bgp open-on-accept - specifies that Advanced Routing Suite will send the Open message when the

TCP connection has completed for configured peers

Syntax

bgp open-on-accept

no bgp open-on-accept

bgp pass-optional-nontrans

Border Gateway Protocol (BGP) Page 87

Mode

BGP Router Configuration

Parameters

none

Description

When the bgp open-on-accept command is configured, Advanced Routing Suite will immediately send

the Open message when the TCP connection has completed for configured peers.

Default

If bgp open-on-accept is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp open-on-accept

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables the open-on-accept feature.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp open-on-accept

(config-router-bgp)# exit

(config)#

bgp pass-optional-nontrans

Name

bgp pass-optional-nontrans - specifies whether to propagate unrecognized, optional, non-transitive

attributes

Syntax

bgp pass-optional-nontrans

no bgp pass-optional-nontrans

Mode

BGP Router Configuration

Parameters

none

Description

Use the bgp pass-optional-nontrans command to specify whether to propagate unrecognized,

optional, non-transitive attributes.

Default

If bgp pass-optional-nontrans is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp pass-optional-nontrans

bgp restart-defer

Border Gateway Protocol (BGP) Page 88

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables the pass-optional-nontrans feature.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp pass-optional-nontrans

(config-router-bgp)# exit

(config)#

bgp restart-defer

Name

bgp restart-defer - configures the time to defer route selection after gracefully restarting

Syntax

bgp restart-defer time-seconds

no bgp restart-defer time-seconds?

Mode

BGP Router Configuration

Parameters

time-seconds - time in seconds between 0 and 4,294,967,295, inclusive

Description

Use the bgp restart-defer command to configure the time in seconds to defer route selection after

gracefully restarting. This is the maximum time to wait for all peers to come back up and send End-Of-RIB

messages. The negative form of this command, no bgp restart-defer, removes the configured

time-seconds value and returns this to its default value of 180 seconds. Note: Specifying a value for

time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If bgp restart-defer is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# bgp restart-defer 180

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the restart-defer time to be 150 seconds.

(config)# router bgp 2222

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# bgp restart-defer 150

(config-router-bgp)# exit

bgp restart-delete-remnants

Border Gateway Protocol (BGP) Page 89

bgp restart-delete-remnants

Name

bgp restart-delete-remnants - turns on BGP’s deletion of kernel remnant routes

Syntax

bgp restart-delete-remnants

no bgp restart-delete-remnants

Mode

BGP Router Configuration

Parameters

none

Description

The bgp restart-delete-remnants command turns on BGP's deletion of kernel remnant routes when

performing a graceful restart after all expected End-of-RIB messages have been received or the restart-defer timer expires. This is used to remove stale routing information that had been retained by the graceful restart procedure.

The negative form of this command, no bgp restart-delete-remnants, turns this feature off. In this

case, stale routing information will be retained after a graceful restart until the kernel remnant hold timer expires. (See the "kernel remnant-holdtime" command.)

Default

If bgp restart-delete-remnants is not specified, it is the same as if the user had specified the

following:

(config-router-bgp)# bgp restart-delete-remnants

Command History

NGC 2.3 - This command was introduced.

Examples

The following example turns off BGP’s deletion of kernel remnant routes.

(config)# router bgp 2222

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# no bgp restart-delete-remnants

(config-router-bgp)# exit

bgp restart-time

Name

bgp restart-time - configures the time advertised within the graceful restart capability when opening a

peering session

Syntax

bgp restart-time time-seconds

no bgp restart-time time-seconds?

bgp restart-timeout

Border Gateway Protocol (BGP) Page 90

Mode

BGP Router Configuration

Parameters

time-seconds - the time in seconds between 0 and 4,294,967,295

Description

Use the bgp restart-time command to configure the time advertised within the graceful restart capability

when opening a peering session. This is the amount of time it takes to restart within the configured peers.

The negative form of this command, no bgp restart-time, removes the configured time-seconds value

and returns this to its default value of 180 seconds. Note: Specifying a value for time-seconds in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If bgp restart-time is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# bgp restart-time 180

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the restart-time to be 150 seconds.

(config)# router bgp 2222

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp restart-time 150

(config-router-bgp)# exit

(config)#

bgp restart-timeout

Name

bgp restart-timeout - configures the time to wait for gracefully restarting peers to come back up

Syntax

bgp restart-timeout time-seconds

no bgp restart-timeout time-seconds?

Mode

BGP Router Configuration

Parameters

time-seconds - the time in seconds between 0 and 4,294,967,295

Description

Use the bgp restart-timeout command to configure the time in seconds to wait for gracefully restarting

peers to come back up. This overrides the value that the peer advertised in the graceful start capability. Once this timeout is reached, Advanced Routing Suite will delete all routes learned from the restarting peer.

The negative form of this command, no bgp restart-timeout, removes the configured time-seconds

bgp router-id

Border Gateway Protocol (BGP) Page 91

value and returns this to its default value of 180 seconds. Note: Specifying a value for time-seconds in the

no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If bgp restart-timeout is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# bgp restart-timeout 180

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the restart-timeout to be 150 seconds.

(config)# router bgp 2222

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp restart-timeout 150

(config-router-bgp)# exit

bgp router-id

Name

bgp router-id - configures a BGP-specific router ID

Syntax

bgp router-id router_id

no bgp router-id router_id

Mode

BGP Router Configuration

Parameters

router_id - a 32-bit integer in dotted-quad notation to be used as the BGP router ID

Description

Use the bgp router-id command to specify a Router ID value that overrides the globally configured

Router ID.

Default

BGP defaults to the globally configured Router ID.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the BGP Router ID to be 1.2.3.4.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# exit

(config)#

bgp send-group-always

Border Gateway Protocol (BGP) Page 92

bgp send-group-always

Name

bgp send-group-always - an internal debugging option that causes BGP packets to be sent via the

code optimized for sending to multiple peers simultaneously, when it makes sense to do so

Syntax

bgp send-group-always

no bgp send-group-always

Mode

BGP Router Configuration

Parameters

none

Description

bgp send-group-always is an internal debugging option. By specifying this command, BGP packets will

be sent via the code optimized for sending to multiple peers simultaneously, when it makes sense to do so.

Use the negative form of this command, no bgp send-group-always, to turn this setting off.

Default

If bgp send-group-always is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp send-group-always

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes BGP packets to be sent via the code optimized for sending to multiple peers simultaneously.

(config)# router bgp 65000

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp send-group-always

(config-router-bgp)# exit

(config)#

bgp tie-break-on-age

Name

bgp tie-break-on-age - specifies that the age of routes should be compared when breaking ties

between BGP routes

Syntax

bgp tie-break-on-age

no bgp tie-break-on-age

clear ip bgp

Border Gateway Protocol (BGP) Page 93

Mode

BGP Router Configuration

Parameters

none

Description

When breaking ties between BGP routes, bgp tie-break-on-age can be used to specify that the age of

the routes should be compared. If this is configured, then older routes are favored over newer routes.

Default

If bgp tie-break-on-age is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no bgp tie-break-on-age

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes BGP to break ties in favor of older routes.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# bgp tie-break-on-age

(config-router-bgp)# exit

(config)#

clear ip bgp

Name

clear ip bgp - resets BGP peering sessions and sends route refresh requests

Syntax

clear ip bgp [peer | *] [soft]?

Mode

User Execution

Parameters

[peer | *] - specify the IPv4 address of a single BGP peer, or specify "*" to clear all peers

soft - optionally specify to send a Route Refresh message (if supported by the peer)

Description

Use the clear ip bgp command to reset BGP peering sessions or to send a Route Refresh request.

Command History

NGC 2.2 - This command was introduced.

default-metric

Border Gateway Protocol (BGP) Page 94

Examples

Example 1

The following example specifies to clear the BGP peer 1.2.3.4.

> clear ip bgp 1.2.3.4

Example 2

The following example specifies to clear all BGP peers and send a Route Refresh message.

> clear ip bgp * soft

default-metric

Name

default-metric - causes a BGP MED to be set on routes when they are advertised to peers

Syntax

default-metric metric

no default-metric metric?

Mode

BGP Router Configuration

Parameters

metric - a 32-bit value ranging from 0 to 4,294,967,295, inclusive

Description

The default-metric command causes a BGP MED to be set on routes when they are advertised to

peers. This value applies to all BGP peers. It can be overridden on a per-peer or per-group basis. The

negative form of this command, no default-metric, removes the configured value. Note: Specifying a

value for metric in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

The default-metric command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes Advanced Routing Suite to advertise a MED value of 50 to its BGP peers.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# default-metric 50

(config-router-bgp)# exit

(config)#

distance

Border Gateway Protocol (BGP) Page 95

Example 2

The following example removes the previously configured default-metric value on the router.

(config)# router bgp 65535

(config-router-bgp)# no default-metric 50

(config-router-bgp)# exit

(config)#

distance

Name

distance - specifies the way that active routes learned from BGP will be selected, compared to other

protocols

Syntax

distance dist

no distance dist?

Mode

BGP Router Configuration

Parameters

dist - an integer between 0 and 255, inclusive

Description

The distance command specifies how active routes that are learned from BGP will be selected, compared

to other protocols. When a route has been learned from more than one protocol, the active route will be selected from the protocol with the lowest distance (or preference).

The negative form of this command, no distance, removes the configured value and returns this to its

default value of 170. Note: Specifying a value for dist in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If distance is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# distance 170

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the global BGP distance (preference) to be 140.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# distance 140

(config-router-bgp)# exit

(config)#

distribute-list

Border Gateway Protocol (BGP) Page 96

Example 2

The following example deletes the globally configured BGP distance (preference) and reverts to the default value of 170.

(config)# router bgp 65535

(config-router-bgp)# no distance 140

(config-router-bgp)# exit

(config)#

distribute-list

Name

distribute-list - provides policy filtering for BGP routes

Syntax

distribute-list access_list_name [ in | out [protocol]? ]

no distribute-list access_list_name [ in | out [protocol]? ]

Mode

BGP Router Configuration

Parameters

access_list_name - the name of an access list

in | out - specifies whether the route applies to imported (in) or exported (out) routes

protocol - for exported routes (out), optionally specify a redistributed protocol to filter. Valid values include:

aggregate, bgp, kernel, ospf, ospf-ase, rip, and static.

Description

The distribute-list command provides a policy filtering mechanism for BGP routes. If the distribute list

configured in this command is specified with the in keyword, then the filter will apply to all imported routes

(that is to say, routes learned from BGP neighbors). If the distribute list configured in this command is

specified with the out keyword, then the filter applies to exported routes (that is to say, routes announced to

BGP neighbors).

To delete a configured distribute list, use the negative form of the command. Note: All arguments of the original command must be supplied in order for the entry to be deleted.

distribute-list in

The distribute-list in command configures a BGP import policy (in other words, a policy for BGP to

apply to incoming updates). If an inbound distribute-list is configured, then each route received from

other BGP neighbors will be evaluated against this inbound list. If the route matches the criteria specified by the inbound list, then the route is imported. If the route does not match the inbound list criteria, then the route is rejected. A route matches the inbound list criteria if it is permitted when evaluated against the referenced access list.

distribute-list out

The distribute-list out command is used to configure export policy for BGP routes. Outbound

distribute lists look similar to inbound distribute lists, except that they allow you to optionally specify a protocol, or more correctly, a route source. This allows you to filter exported routes based on whether they were learned from RIP, OSPF, OSPF-ASE or were aggregate, static, or kernel routes. At most one

distribute-list out command that does not reference a protocol can be specified. If an outbound

distribute list is configured without referencing a protocol, then when a route is being considered for export

enable

Border Gateway Protocol (BGP) Page 97

to BGP neighbors, it must be permitted by the access list referenced in the distribute list. If instead an outbound distribute list is configured that references a protocol, and if the route being considered for export originated from the referenced protocol, then the route must be permitted by the access list referenced in the distribute list. If more of both types of lists are present, then the route need only be permitted by the access list referenced by one of the outbound distribute lists.

It should be noted that an outbound distribute list has no effect in the absence of a "redistribute" ("redistribute" on page 147) command. Outbound distribute lists can be thought of as a way to further refine the export policy expressed with a "redistribute" ("redistribute" on page 147) command.

The negative form of this command, no distribute-list, removes the configured list. You must

specify either in or out in the negative form. For outbound distribute lists, specifying a protocol is optional.

If the protocol is not specified, then all distribute lists referencing the specified access list will be deleted.

Default

Distribute lists are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures two distribute lists. The first distribute list defines import policy using access list "alist1". The second distribute list defines export policy for static routes.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# distribute-list alist1 in

(config-router-bgp)# distribute-list alist2 out static

(config-router-bgp)# exit

(config)#

See Also

"redistribute" ("redistribute" on page 147)

enable

Name

enable - enables BGP

Syntax

enable

no enable

Mode

BGP Router Configuration

Parameters

none

Description

The enable command enables BGP configuration on a router. The negative form of this command, no

enable, disables BGP. This command is useful when you want BGP turned "on" on a router, but you want

your BGP router configuration details to be turned "off."

maximum-routes

Border Gateway Protocol (BGP) Page 98

Default

If enable is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# enable

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables BGP on the router. Note that BGP will still be turned "on" on AS 65535, but configuration state will be turned off.

(config)# router bgp 65535

(config-router-bgp)# no enable

(config-router-bgp)# exit

(config)#

maximum-routes

Name

maximum-routes - specifies the maximum number of routes that BGP will accept for installation into the

Advanced Routing Suite routing information base (RIB)

Syntax

maximum-routes number

no maximum-routes number?

Mode

BGP Router Configuration

Parameters

number - an integer between 1 and 4,294,967,295, inclusive

Description

The maximum-routes command specifies the maximum number of routes that BGP will accept for

installation into the Advanced Routing Suite RIB.

Default

If maximum-routes is not specified, then BGP will accept an unlimited number of routes for installation into

the Advanced Routing Suite RIB. The negative form of this command, no maximum-routes, removes the

configured value and allows an unlimited number of routes. Note: Specifying a value for number in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, Advanced Routing Suite will install a maximum of 50 routes learned from BGP into the routing table.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

neighbor add-communities

Border Gateway Protocol (BGP) Page 99

(config-router-bgp)# maximum-routes 50

(config-router-bgp)# exit

(config)#

neighbor add-communities

Name

neighbor add-communities - adds a community to BGP

Syntax

neighbor ip_address add-communities id

no neighbor ip_address add-communities id

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format.

id - the community set ID to be added

Description

Use the neighbor add-communities command to add a BGP community to this peer. BGP communities

are configured with the ip community-set command in Global Configuration mode. The id value

corresponds with the ID of the community set.

Default

Community sets are not added or configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes the communities described in "comm1" to be sent in BGP updates to peer 1.2.3.4.

(config)# router bgp 60004

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 add-communities comm1

(config-router-bgp)# exit

(config)#

neighbor aggregator-id

Name

neighbor aggregator-id - specifies whether the router-id in the aggregator attribute should be 0

neighbor aggregator-id

Border Gateway Protocol (BGP) Page 100

Syntax

neighbor ip_address aggregator-id

no neighbor ip_address aggregator-id

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

Description

When Advanced Routing Suite aggregates a route, the aggregator ID attribute, along with the Router ID are

sent. neighbor aggregator-id allows you to specify whether the Router ID in the aggregator attribute

should be 0, instead of the ID of the router.

The negative of this command, no neighbor aggregator-id, specifies that the router ID in the

aggregator attribute should be the ID of the router.

Default

If neighbor aggregator-id is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] aggregator-id

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes BGP to set the value of the aggregator ID to 0.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 aggregator-id

(config-router-bgp)# exit

(config)#

Example 2

The following example causes BGP to set the value of the aggregator ID to the router ID.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# no neighbor 1.2.3.4 aggregator-id

(config-router-bgp)# exit

(config)#

neighbor allow

Border Gateway Protocol (BGP) Page 101

neighbor allow

Name

neighbor allow - permits peer connections from addresses in the specified access-list

Syntax

neighbor group-name allow access_list remote-as as-number

no neighbor group-name allow access_list

Mode

BGP Router Configuration

Parameters

group-name - the name of a BGP peer group specified as a string of characters

access_list - the name of the access list from which peer connections will be made

remote-as as_num - the autonomous system (AS) number of a BGP peer. This can be an integer from 1

to 65535, inclusive.

Description

The neighbor allow command permits peer connections from addresses in the specified access list.

Access lists are configured with the ip access-list command in Global Configuration mode. The

access_list value corresponds with the ID of the access list.

Note: You must specify the remote Autonomous System again in this command, even if it was previously

specified in the neighbor command.

Default

The allow command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example allows incoming peering connections from those peers specified in access-list-1.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor group1 allow access-list-1 remote-as 5

(config-router-bgp)# exit

(config)#

Example 2

The following example will cease allowing incoming peering connections from access_list_1.

(config)# router bgp 65535

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# no neighbor 1.2.3.4 allow access-list-1 remote-as 5

neighbor as-loop

Border Gateway Protocol (BGP) Page 102

(config-router-bgp)# exit

(config)#

See Also

Chapter 25 Access Lists

neighbor as-loop

Name

neighbor as-loop - specifies the number of times an autonomous system may appear in an AS path

Syntax

neighbor [ ip_address | group-name ] as-loop loop-count

no neighbor [ ip_address | group-name ] as-loop loop-count?

Mode

BGP Router Configuration

Parameters

ip_address - the address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

loop-count - an integer in the range 1 to 10, inclusive

Description

The neighbor as-loop command specifies the number of times this autonomous system can appear in a

peer or peer group AS path. loop-count is an integer in the range 1 to 10, inclusive. The negative form of this

command, no neighbor as-loop, removes the configured loop-count value and returns this to its default

value of 1.

Notes:

Specifying a value for loop-count in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

This command should not be used in normal operations.

Default

If neighbor as-loop is not specified for an autonomous system setting, it is the same as if the user had

specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] as-loop 1

Command History

NGC 2.2 - This command was introduced.

Examples

In this example, the number of loops for peer 1.2.3.4 is set to 2.

(config)# router bgp 7476

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 as-loop 2

neighbor as-override

Border Gateway Protocol (BGP) Page 103

(config-router-bgp)# exit

(config)#

neighbor as-override

Name

neighbor as-override - configures all occurrences of a peer’s AS to be replaced with one from an

export

Syntax

neighbor [ ip_address | group-name ] as-override

no neighbor [ ip_address | group-name ] as-override

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

Description

The neighbor as-override command specifies that all occurrences of a peer’s AS should be replaced

with our address. The negative form of this command, no neighbor as-override, removes this

configuration.

Default

If neighbor as-override is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] as-override

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns on the AS Override feature.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 as-override

neighbor aspath-prepend

Name

neighbor aspath-prepend - specifies the number of times that this router will prepend its AS number to

a route’s AS Path when it send the route to an external peer

neighbor capability orf comm-filter

Border Gateway Protocol (BGP) Page 104

Syntax

neighbor ip_address aspath-prepend num

no neighbor ip_address aspath-prepend num

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

num - an integer between 1 and 25, inclusive

Description

Use the neighbor aspath-prepend command to configure the number of times that this router will

prepend its AS number to a route’s AS Path when it sends the route to an external peer. Larger values are typically used to bias upstream peers’ route selection. Most routers will prefer routes with shorter AS Path. Using this command, the AS Path that this router sends can be artificially lengthened.

Default

If neighbor aspath-prepend is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] aspath-prepend 1

Note: The BGP protocol specifies you must add your local AS number to the AS_PATH attribute. The aspath-prepend option lets you do it more than once.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, the router is configured to prepend its AS number to a route’s AS Path five times.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 10.1.1.1 remote-as 5

(config-router-bgp)# neighbor 10.1.1.1 aspath-prepend 5

(config-router-bgp)# exit

(config)#

neighbor capability orf comm-filter

Name

neighbor capability orf comm-filter - specifies whether the ORF capability for community filtering

is to be sent to the BGP peer or group, received from the BGP peer or group, or both

Syntax

neighbor [ip_address | group-name] capability orf comm-filter [send | receive | both]

no neighbor [ip_address | group-name] capability orf comm-filter [send | receive | both]

neighbor capability orf extcomm-filter

Border Gateway Protocol (BGP) Page 105

Mode

BGP Router Configuration

Parameters

ip_address - the IPv4 address of a BGP peer specified in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

send | receive | both - specifies the action to take when filtering communities

Description

The neighbor capability orf comm-filter commands specifies whether the ORF capability for

community filtering is to be sent from a BGP peer or group, accepted on a BGP peer or group, or both. The

negative form of this command, no neighbor capability orf comm-filter, removes the capability.

Default

ORF capabilities are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that BGP peer 4.3.2.1 will send the ORF capability for community filtering.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 4.3.2.1 remote-as 65001

(config-router-bgp)# neighbor 4.3.2.1 capability orf comm-filter send

neighbor capability orf extcomm-filter

Name

neighbor capability orf extcomm-filter - specifies whether the ORF capability for extended

community filtering is to be sent to the BGP peer or group, received from the BGP peer or group, or both

Syntax

neighbor [ip_address | group-name] capability orf extcomm-filter [send | receive | both]

no neighbor [ip_address | group-name] capability orf extcomm-filter [send | receive | both]

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

send | receive | both - specifies the action to take when filtering extended communities

neighbor capability orf prefix-filter

Border Gateway Protocol (BGP) Page 106

Description

The neighbor capability orf extcomm-filter commands specifies whether the ORF capability for

extended community filtering is to be sent from a BGP peer or group, accepted on a BGP peer or group, or

both. The negative form of this command, no neighbor capability orf extcomm-filter, removes

the capability.

Note: When configured in BGP Router Configuration mode, the address family sent will be IPv4 unicast.

Default

ORF capabilities are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that BGP peer 4.3.2.1 will send the ORF capability for extended community filtering.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 4.3.2.1 remote-as 65001

(config-router-bgp)# neighbor 4.3.2.1 capability orf extcomm-filter send

neighbor capability orf prefix-filter

Name

neighbor capability orf prefix-filter - specifies whether the ORF capability for prefix filtering is

to be sent from and/or received on the BGP peer or group

Syntax

neighbor [ip_address | group-name] capability orf prefix-filter [send | receive | both]

no neighbor [ip_address | group-name] capability orf prefix-filter [send | receive | both]

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

send | receive | both - specifies the action to take when filtering prefixes

Description

The neighbor capability orf prefix-filter commands specifies whether the ORF capability for

prefix filtering is to be sent from a BGP peer or group, accepted on a BGP peer or group, or both. The

negative form of this command, no neighbor capability orf prefix-filter, removes the capability.

Default

ORF capabilities are not explicitly configured by default.

neighbor cluster-id

Border Gateway Protocol (BGP) Page 107

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that BGP peer 4.3.2.1 will send the ORF capability for prefix filtering.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 4.3.2.1 remote-as 65001

(config-router-bgp)# neighbor 4.3.2.1 capability orf prefix-filter send

neighbor cluster-id

Name

neighbor cluster-id - specifies the route reflection cluster ID for a peer or peer group in BGP

Syntax

neighbor [ip_address | group-name] cluster-id router-id

no neighbor [ip_address | group-name] cluster-id router-id

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

router-id - a router ID in dotted-quad format used by route reflectors to prevent route propagation loops

within the cluster

Description

The neighbor cluster-id command specifies the route reflection cluster ID for a BGP peer or peer

group. The cluster ID defaults to be the same as the router ID. If a router is to be a route reflector, then a single cluster ID should be selected and configured on all route reflectors in the cluster. If there is only one route reflector in the cluster, the cluster-id setting can be omitted because the default will suffice.

The only constraints on the choice of cluster ID are the following:

IDs of clusters within an Autonomous System (AS) must be unique within that AS.

The cluster ID must not be 0.0.0.0

Choosing the cluster ID to be the router ID of one router in the cluster will always fulfill these criteria. If there is only one route reflector in the cluster, the "cluster ID" setting can be omitted, because the default will suffice.

When a route is received, if it does not have all of the local cluster IDs, then it is accepted. Additionally, when a route is reflected, all of the locally configured cluster IDs that are not already present on the route are prepended to the CLUSTER_LIST.

Notes:

If configuration results in a change in the set of cluster IDs on the box, then the "clear ip bgp" ("clear ip bgp" on page 93) command is necessary to get the change to effect previous learned routes/announcements.

neighbor distance

Border Gateway Protocol (BGP) Page 108

You must specify either a remote AS or a peer group before configuring a cluster ID.

Default

The cluster ID value defaults to the router ID.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a cluster ID of 2.2.2.2 for peer 4.3.2.1.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 4.3.2.1 cluster ID 2.2.2.2

(config-router-bgp)# exit

(config)#

neighbor distance

Name

neighbor distance - specifies the way that active routes learned from BGP will be selected, compared

to other protocols, within a BGP peer

Syntax

neighbor [ ip_address | group-name ] distance dist

no neighbor [ ip_address | group-name ] distance dist

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

dist - an integer between 0 and 255, inclusive

Description

The neighbor distance command specifies how active routes within the specified BGP peer that are

learned from BGP will be selected, compared to other protocols. When a route has been learned from more than one protocol, the active route will be selected from the protocol with the lowest distance (or preference).

The negative form of this command, no neighbor distance, removes the configured value and returns

this to its default value of 170.

Default

If neighbor distance is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] distance 170

neighbor dynamic

Border Gateway Protocol (BGP) Page 109

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the global BGP distance (or preference) to be 140 and the BGP distance (or preference) for peer 1.2.3.4 to be 80.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# distance 140

(config-router-bgp)# neighbor 1.1.1.1 remote-as 5

(config-router-bgp)# neighbor 1.1.1.1 distance 80

(config-router-bgp)# exit

(config)#

neighbor dynamic

Name

neighbor dynamic - activates the dynamic capability for this peer

Syntax

neighbor [ip_address | group-name] dynamic

no neighbor [ip_address | group-name] dynamic

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use the neighbor dynamic to turn on dynamic capabilities for this peer. The negative form of this

command, no neighbor dynamic, turns the dynamic capability off for a peer.

Default

If neighbor dynamic is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] dynamic

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns on the dynamic capability feature for 1.2.3.4.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

neighbor enable

Border Gateway Protocol (BGP) Page 110

(config-router-bgp)# neighbor 1.2.3.4 dynamic

(config-router-bgp)# exit

neighbor enable

Name

neighbor enable - enables a BGP peer or peer group

Syntax

neighbor [ip_address | group-name] enable

no neighbor [ip_address | group-name] enable

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use the neighbor enable command to explicitly enable a BGP peer or peer group. Use the negative form

of this command, no neighbor enable, to explicitly disable a peering session. Configuration will still be

retained.

Default

If neighbor enable is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] enable

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables BGP for peer 1.2.3.4.

(config)# router bgp 65535

(config-router-bgp)# no neighbor 1.2.3.4 enable-peer

(config-router-bgp)# exit

(config)#

neighbor end-of-rib

Name

neighbor end-of-rib - activates the End-of-RIB capability for a peer

Syntax

neighbor [ip_address | group-name] end-of-rib

neighbor export-localpref

Border Gateway Protocol (BGP) Page 111

no neighbor [ip_address | group-name] end-of-rib

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use the neighbor end-of-rib command to configure the End of RIB capability for a peer. This is a

special form of Graceful Restart that sends End-of-RIB messages, but does not perform graceful restart operations.

Default

If neighbor end-of-rib is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] end-of-rib

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the End-of-RIB option for 1.2.3.4.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 end-of-rib

(config-router-bgp)# exit

neighbor export-localpref

Name

neighbor export-localpref - specifies the Local_Pref value that is sent in the BGP update packet

when advertising a route to an internal or confederation peer

Syntax

neighbor [ip_address | group-name] export-localpref local_pref

no neighbor [ip_address | group-name] export-localpref local_pref?

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP address is specified (for example 256.1.1.1), it will be read as a group name.

neighbor graceful-restart

Border Gateway Protocol (BGP) Page 112

local_pref - an integer from 0 to 4,294,967,295, inclusive

Description

Use the neighbor export-localpref command to configure the Local_Pref value that is sent in the

BGP Update packet when advertising a route to an internal or confederation peer. This value overrides the calculated Local_Pref on the route. BGP will export the route with the calculated Local_Pref value.

The negative form of this command, no neighbor export-localpref, removes the configured

local_pref value and returns this to its default value of 100. Note: Specifying a value for local_pref in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If neighbor export-localpref is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] export-localpref 100

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the export Local_Pref value to be 200.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 1.1.1.1 remote-as 5

(config-router-bgp)# neighbor 1.1.1.1 export-localpref 200

(config-router-bgp)# exit

(config)#

neighbor graceful-restart

Name

neighbor graceful-restart - configures the Graceful Restart capability for the family/sub address

family pair

Syntax

neighbor [ip_address | group-name] graceful-restart

no neighbor [ip_address | group-name] graceful-restart

Mode

Address Family Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use restart to turn on or off the Graceful Restart capability for the family/sub address family pair.

Note: For graceful restart to be useful beyond IPv4 unicast, the corresponding multi-protocol capability must also be in effect.

neighbor ignore-leading-as

Border Gateway Protocol (BGP) Page 113

Default

If neighbor graceful-restart is not specified, it is the same as if the user had specified the following:

(config-router-af)# no neighbor [ip_address | group-name] graceful-restart

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example turns graceful-restart on for IPv4 multicast.

(config)# router bgp 61111

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# address-family ipv4 multicast

(config-router-af)# neighbor 1.2.3.4 graceful-restart

(config-router-af)# exit

(config)#

neighbor ignore-leading-as

Name

neighbor ignore-leading-as - directs Advanced Routing Suite to keep route server routes

Syntax

neighbor [ip_address | group-name] ignore-leading-as

no neighbor [ip_address | group-name] ignore-leading-as

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Some routers are capable of propagating routes without appending their own autonomous system number

to the AS Path. By default, Advanced Routing Suite will drop such routes. The neighbor

ignore-leading-as command allows Advanced Routing Suite to keep these routes. This command

should be used only if there is no doubt that these peers are route servers and not normal routers.

Default

If neighbor ignore-leading-as is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] ignore-leading-as

Command History

NGC 2.2 - This command was introduced.

neighbor import-localpref

Border Gateway Protocol (BGP) Page 114

Examples

The following example enables the ignore-leading-as feature.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 1.1.1.1 remote-as 5

(config-router-bgp)# neighbor 1.1.1.1 ignore-leading-as

(config-router-bgp)# exit

(config)#

neighbor import-localpref

Name

neighbor import-localpref - specifies the Local_Pref value that is received in the BGP Update

packet when advertising a route to an external or confederation peer

Syntax

neighbor [ip_address | group-name] import-localpref local_pref

no neighbor [ip_address | group-name] import-localpref local_pref?

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

local_pref - an integer from 0 to 4,294,967,295, inclusive

Description

Use the neighbor import-localpref command to configure the Local_Pref value that is sent in the

BGP Update packet when advertising a route to an external or confederation peer. This value overrides the calculated Local_Pref on the route. BGP will import the route with the calculated Local_Pref value.

The negative form of this command, no neighbor import-localpref, removes the configured

local_pref value and returns this to its default value of 100. Note: Specifying a value for local_pref in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If neighbor import-localpref is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] import-localpref 100

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the import Local_Pref value to be 200.

(config)# router bgp 65535

neighbor keep

Border Gateway Protocol (BGP) Page 115

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 1.1.1.1 remote-as 5

(config-router-bgp)# neighbor 1.1.1.1 import-localpref 200

(config-router-bgp)# exit

(config)#

neighbor keep

Name

neighbor keep - specifies the action to take when routes are received containing a router’s own

autonomous system (AS) number

Syntax

neighbor [ip_address | group-name] keep [ normal | all | none ]

no neighbor [ip_address | group-name] keep [ normal | all | none ]

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

normal - discards routes that contain a router’s own autonomous system number

all - retains routes learned from a peer even if the routes’ AS paths contain the router's own AS number

none - discards routes that have failed import policy

Description

Use neighbor keep to specify whether to keep routes containing a router's own autonomous system

number or routes that have failed import policy

normal causes Advanced Routing Suite to discard routes that contain a router's own autonomous system

number. Also by default, Advanced Routing Suite will retain routes that have failed import policy so that these routes may be re-examined when import policy is changed during reconfiguration.

all causes Advanced Routing Suite to retain all routes that contain the router's own autonomous system

number. In combination with the "loops" command in the autonomous system command, this can allow a healing of a partitioned AS via the Internet.

none causes Advanced Routing Suite to discard all routes that have failed import policy. This can result in a

substantial saving in space in the router. In order to re-acquire discarded routes, the "clear ip bgp" ("clear ip bgp" on page 93) command should be issued to either manually flap peering sessions or issue a Route

Refresh request (with the "soft" keyword).

Default

If neighbor keep is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] keep normal

Command History

NGC 2.2 - This command was introduced.

neighbor keepalives-always

Border Gateway Protocol (BGP) Page 116

Examples

Example 1

The following example causes Advanced Routing Suite to keep routes learned from this peer even if they container our own AS number.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 keep all

(config-router-bgp)# exit

(config)#

Example 2

The following example causes Advanced Routing Suite to revert to the value of "normal" for keep.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# no neighbor 1.2.3.4. keep all

(config-router-bgp)# exit

(config)#

neighbor keepalives-always

Name

neighbor keepalives-always - causes Advanced Routing Suite to always send keepalives

Syntax

neighbor [ip_address | group-name] keepalives-always

no neighbor [ip_address | group-name] keepalives-always

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

The neighbor keepalives-always command causes Advanced Routing Suite to always send

keepalives, even when an update may have correctly substituted for one. This command allows inter-operability with routers that do no completely obey the protocol specifications on this point.

Default

If neighbor keepalives-always is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address |

group-name] keepalives-always

neighbor local-as

Border Gateway Protocol (BGP) Page 117

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables the keepalives-always feature for peer 1.2.3.4.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 keepalives-always

(config-router-bgp)# exit

(config)#

neighbor local-as

Name

neighbor local-as - identifies the autonomous system (AS) that Advanced Routing Suite is

representing to a peer

Syntax

neighbor ip_address local-as as_num

no neighbor ip_address local-as as_num

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

as_num - a number between 1 and 65535, specifying a set of routers under a single technical

administration and assigned by the Internet Assigned Numbers Authority

Description

The neighbor local-as command identifies the AS that Advanced Routing Suite is representing to a

group of peers.

Note: This command is valid only for external peers.

Default

The default AS number for this command is the current AS (configured with the router bgp command in

Global Configuration mode).

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes BGP to represent itself to the peer 1.2.3.4 as being in AS 100.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

neighbor log-up-down

Border Gateway Protocol (BGP) Page 118

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 local-as 100

(config-router-bgp)# exit

(config)#

Example 2

The following example causes BGP to cease representing itself to peer 1.2.3.4 as being in AS 100. Instead, it will represent itself as being in AS 64512.

(config)# router bgp 64512

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# no neighbor 1.2.3.4 local-as 100

(config-router-bgp)# exit

(config)#

neighbor log-up-down

Name

neighbor log-up-down - causes a message to be logged via the syslog mechanism whenever a BGP

peer or peer group enters or leaves the Established state

Syntax

neighbor [ ip_address | group-name ] log-up-down

no neighbor [ ip_address | group-name ] log-up-down

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

neighbor log-up-down specifies whether a message will be logged via the syslog mechanism whenever

a BGP peer or peer group enters or leaves the Established state.

Default

If neighbor log-up-down is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] log-up-down

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes a message to be logged in syslog whenever this peer leaves or enters the Established state.

(config)# bgp router 65535

(config-router-bgp)# bgp router-id 1.1.1.1

neighbor maximum-routes

Border Gateway Protocol (BGP) Page 119

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 log-up-down

(config-router-bgp)# exit

(config)#

neighbor maximum-routes

Name

neighbor maximum-routes - specifies the maximum number of routes that BGP will accept for

installation into the Advanced Routing Suite routing information base (RIB)

Syntax

neighbor [ip_address | group-name] maximum-routes num [threshold]? [(restart time-minutes) | (warning-only)]?

no neighbor [ip_address | group-name] maximum-routes num? [threshold]? [(restart time-minutes) | (warning-only)]?

Mode

BGP Router Configuration

Parameters

ip_address - the address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

num - an integer between 1 and 4,294,967,295, inclusive

threshold - a percentage

restart time-minutes - an integer from 1 to 65535, inclusive, specifying a number of minutes. This

specifies the amount of time that will elapse before a restart occurs.

warning-only - specifies to log a warning message, stop accepting routes, and keep the established

peering session

Description

The neighbor maximum-routes command configures the maximum number of routes that a non-group

peer or peers in a peer group will accept for installation into Advanced Routing Suite. You can also specify a threshold percentage. When this percentage of maximum routes are accepted, the configured action will occur. In addition, an action can be configured to occur when this maximum number is exceeded. The action can be one of the following:

If warning-only is specified, log a warning message and stop accepting additional routes, but still

keep the established peer session

if restart is specified, close the peer session and restart after the specified number of minutes

if neither warning-only nor restart is configured, close the peer session and keep this in idle state

until the "clear ip bgp" ("clear ip bgp" on page 93) command is issued

The negative form of this command, no neighbor maximum-routes, removes the configure route limit

and returns this setting to its default value of unlimited

Default

If neighbor maximum-routes is not specified, it is the same as if the user had specified the following:

neighbor metric-out

Border Gateway Protocol (BGP) Page 120

(config-router-bgp)# neighbor [ip_address | group-name] maximum-routes 4294967295

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes Advanced Routing Suite to install a maximum of 1000 routes learned from peer 1.2.3.4 into the routing table. If this amount is exceeded, then the BGP peering session will restart after 10 minutes.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 maximum-routes 1000 restart 10

(config-router-bgp)# exit

(config)#

Example 2

The following example causes Advanced Routing Suite to install a maximum of 1000 routes learned from peer 10.23.12.13 into the routing table. If more than 80% of these routes are installed, then Advanced

Routing Suite will close the peering session and keep it down until a clear ip bgp command is specified.

(config)# router bgp 65535

(config-router-bgp)# neighbor 10.23.12.13 remote-as 5

(config-router-bgp)# neighbor 10.23.12.13 maximum-routes 1000 80

(config-router-bgp)# exit

(config)#

Example 3

The following example causes Advanced Routing Suite to install a maximum of 1000 routes learned from peer 4.3.2.1 into the routing table. If this number is exceeded, then Advanced Routing Suite will log a warning message and stop accepting additional routes.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 4.3.2.1 remote-as 5

(config-router-bgp)# neighbor 4.3.2.1 maximum-routes 1000 warning-only

(config-router-bgp)# exit

(config)#

neighbor metric-out

Name

neighbor metric-out - causes BGP to send a metric value when routes are advertised to peers

Syntax

neighbor ip_address metric-out num

no neighbor ip_address metric-out num?

neighbor multi-protocol-nexthop

Border Gateway Protocol (BGP) Page 121

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

num - an integer between 0 and 4,294,967,295, inclusive

Description

The neighbor metric-out command causes a BGP metric (MED) value to be set on routes when they

are advertised to peers. The negative form of this command, no neighbor metric-out, removes the

configured num value. Note: Specifying a value for num in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If neighbor metric-out is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] metric-out

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a metric value of 50 for routes advertised to peers.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 metric-out 50

(config-router-bgp)# exit

(config)#

neighbor multi-protocol-nexthop

Name

neighbor multi-protocol-nexthop - specifies whether to send a standard BGP nexthop when only

sending multi-protocol BGP routes

Syntax

neighbor [ip_address | group-name] multi-protocol-nexthop

no neighbor [ip_address | group-name] multi-protocol-nexthop

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

neighbor next-hop-self

Border Gateway Protocol (BGP) Page 122

Description

According to the BGP multi-protocol specification RFC 2858, when a BGP Speaker is only sending multi-protocol routes and is not sending any reachability in the standard BGP NLRI field, it is not necessary to send the standard BGP NEXT_HOP path attribute. Unfortunately, some well-deployed implementations have a bug where this field must be present even if it is ignored.

By default, Advanced Routing Suite will send the standard NEXT_HOP field, even when only multi-protocol routes are being sent. If the reachability is IPv4, the NEXT_HOP field will be the same as the multi-protocol nexthop. In the case of non-IPv4 reachability, the standard NEXT_HOP field will contain "0.0.0.0".

Default

If neighbor multi-protocol-nexthop is not specified, it is the same as if the user had specified the

following:

(config-router-bgp)# neighbor [ip_address | group-name] multi-protocol-nexthop

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a standard BGP nexthop will be sent when only sending multi-protocol BGP routes.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 multi-protocol-nexthop

(config-router-bgp)# exit

(config)#

neighbor next-hop-self

Name

neighbor next-hop-self - specifies whether this neighbor’s next hop should be the router's own

address on advertisement

Syntax

neighbor [ip_address | group-name] next-hop-self

no neighbor [ip_address | group-name] next-hop-self

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use the neighbor next-hop-self command to set this group's next hop to the router's own address

even if it would normally be possible to send a third-party next hop. Specifying this command an cause

neighbor orf comm-list

Border Gateway Protocol (BGP) Page 123

inefficient routes to be followed. It might be needed in some cases to deal with improperly bridged interconnect media (in cases where the routers on the "shared" medium do not really have full connectivity to each other), or when political situations cause broken links.

Default

If neighbor next-hop-self is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address |

group-name] next-hop-self

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that the neighbor will the router’s own address as the next hop.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 10.132.10.15

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 next-hop-self

(config-router-bgp)# exit

(config)#

neighbor orf comm-list

Name

neighbor orf comm-list - sends a communities ORF message with the communities filter to the

specified BGP peer

Syntax

neighbor ip_address orf comm-list comm-list-name

no neighbor ip_address orf comm-list comm-list-name

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

comm-list-name - the name of a community list

Description

The neighbor orf comm-list commands sends a communities ORF message with the communities

filter specified by the community list name to the specified peer. The negative form of this command, no

neighbor orf comm-list, stops the sending of this information.

Note: When configured in BGP Router Configuration mode, the address family sent will be IPv4 unicast.

Default

ORF messages are not sent by default.

neighbor orf extcomm-list

Border Gateway Protocol (BGP) Page 124

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that BGP peer 4.3.2.1 will send and receive ORF capability for community filtering information. In addition, a communities ORF message with the filter specified by community list comm1 will be sent to peer 4.3.2.1.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 4.3.2.1 remote-as 65001

(config-router-bgp)# neighbor 4.3.2.1 capability orf comm-filter both

(config-router-bgp)# neighbor 4.3.2.1 orf comm-list comm1

neighbor orf extcomm-list

Name

neighbor orf extcomm-list - sends an extended communities ORF message with the filter specified

by the extended community list name to the specified BGP peer

Syntax

neighbor ip_address orf extcomm-list extcomm-list-name

no neighbor ip_address orf extcomm-list extcomm-list-name

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

extcomm-list-name - the name of an extended community list

Description

The neighbor orf extcomm-list commands sends an extended communities ORF message with the

filter specified by the extended community list name to the specified peer. The negative form of this

command, no neighbor orf extcomm-list, stops the sending of this information.

Note: When configured in BGP Router Configuration mode, the address family sent will be IPv4 unicast.

Default

ORF messages are not sent by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that BGP peer 4.3.2.1 will send and receive ORF capability for extended community filtering information. In addition, an extended communities ORF message with the filter specified by extended community list extcomm1 will be sent to peer 4.3.2.1.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

neighbor orf prefix-list

Border Gateway Protocol (BGP) Page 125

(config-router-bgp)# neighbor 4.3.2.1 remote-as 65001

(config-router-bgp)# neighbor 4.3.2.1 capability orf extcomm-filter both

(config-router-bgp)# neighbor 4.3.2.1 orf extcomm-list extcomm1

neighbor orf prefix-list

Name

neighbor orf prefix-list - sends a prefixes ORF message with the filter specified by the prefix list

name to the specified BGP peer

Syntax

neighbor ip_address orf prefix-list prefix-list-name

no neighbor ip_address orf prefix-list prefix-list-name

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

prefix-list-name - the name of a prefix list

Description

The neighbor orf prefix-list commands sends a prefixes ORF message with the filter specified by

the prefix list name to the specified peer. The negative form of this command, no neighbor orf

prefix-list, stops the sending of this information.

Note: When configured in BGP Router Configuration mode, the address family sent will be IPv4 unicast.

Default

ORF messages are not sent by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that BGP peer 4.3.2.1 will send and receive ORF capability for prefixes filtering information. In addition, a prefixes ORF message with the filter specified by prefix list preflist1 will be sent to peer 4.3.2.1.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 4.3.2.1 remote-as 65001

(config-router-bgp)# neighbor 4.3.2.1 orf capability prefix-filter both

(config-router-bgp)# neighbor 4.3.2.1 orf prefix-list preflist1

neighbor out-delay

Border Gateway Protocol (BGP) Page 126

neighbor out-delay

Name

neighbor out-delay - specifies the amount of time that a route must be present in the Advanced

Routing Suite routing database before it is exported to BGP

Syntax

neighbor ip_address [out-delay time-seconds ]

no neighbor ip_address [out-delay time-seconds ]?

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

out-delay time-seconds - the number of seconds, specified as an integer between 0 and

4,294,967,295, inclusive. This option defaults to 0 and is, thus, displayed above as optional.

Description

Use the neighbor out-delay command to damp route fluctuations. The out-delay time is the amount of

time that a route must be present in the Advanced Routing Suite routing database before it is exported to BGP.

Note: Weighted Route Damping may be better suited for improving overall network stability. The use of this option may delay route convergence for well-behaved routers.

Default

This command is not explicitly configured by default; however, if a neighbor address is configured, the out-delay time will default to 0.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables an out-delay value of 10 seconds on the neighbor 1.2.3.4

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 out-delay 10

(config-router-bgp)# exit

(config)#

neighbor passive

Name

neighbor passive - prevents Advanced Routing Suite from ever trying to open a BGP connection with

peers in this group

neighbor password

Border Gateway Protocol (BGP) Page 127

Syntax

neighbor [ ip_address | group-name ] passive

no neighbor [ ip_address | group-name ] passive

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

The neighbor passive command prevents Advanced Routing Suite from trying to initiate a BGP

connection with peers in this group. Instead, the router will wait for the peer to initiate a connection.

This command was introduced to handle a problem in BGP3 and earlier, in which two peers might both attempt to initiate a connection at the same time. This problem has been correct in the BGP4 protocol, and, thus, this command is not needed with BGP 4 sessions.

Note: If the neighbor passive command is applied to both sides of a peering session, the session will

never be established. For this reason, and because it is generally not needed, the use of neighbor

passive is discouraged.

Default

If neighbor passive is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] passive

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, BGP will never initiate a connection with the peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 passive

(config-router-bgp)# exit

(config)#

neighbor password

Name

neighbor password - configures a TCP-MD5 password for a peer or peer group

Syntax

neighbor [ ip_address ] password key

no neighbor [ ip_address ] password key

neighbor pedantic

Border Gateway Protocol (BGP) Page 128

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

key - a string of characters

Description

The neighbor password command allows you to set a TCP-MD5 password for a peer or peer group. This

feature requires OS support of the TCP MD5 Signature Extension (RFC 2385). Note: You must first configure either a remote AS or a peer group before configuring an authentication password.

Default

A password is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a TCP-MD5 password of "abc" for this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 password abc

(config-router-bgp)# exit

(config)#

Example 2

The following example removes the authentication for peer 1.2.3.4.

(config)# router bgp 65535

(config-router-bgp)# no neighbor 1.2.3.4 password abc

(config-router-bgp)# exit

(config)#

neighbor pedantic

Name

neighbor pedantic - turns on extra, non-critical logging about malformed BGP update messages that

are being ignored

Syntax

neighbor [ip_address | group-name] pedantic

no neighbor [ip_address | group-name] pedantic

Mode

BGP Router Configuration

neighbor peer-group

Border Gateway Protocol (BGP) Page 129

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

This command turns on extra non-critical logging about malformed BGP updates that are being ignored.

Default

If neighbor pedantic is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] pedantic

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns on pedantic logging for this neighbor.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 pedantic

(config-router-bgp)# exit

neighbor peer-group

Name

neighbor peer-group - creates a BGP peer group

Syntax

neighbor group-name peer-group

no neighbor group-name peer-group

neighbor ip_address peer-group pgname

no neighbor ip_address peer-group pgname

Mode

BGP Router Configuration

Parameters

group-name - a string of characters indicating the name of a BGP peer group

ip_address - an IPv4 address to add to a peer group. IPv4 addresses are specified in dotted-quad

format.

pgname - the name of a peer group into which you want the neighbor added. The peer group name is

specified using the neighbor name peer-group command, and that command must be specified before

neighbors can be added to it.

neighbor preference2

Border Gateway Protocol (BGP) Page 130

Description

Use the neighbor peer-group command to create a peer group. BGP peers can then be added to that

group. After this command is issued, peers are added to the group using the neighbor ip_address

peer-group name command. All peers within a group must have the same AS number.

Note: Once you put a neighbor in a group, it loses all options previously configured on the neighbor, except for its AS number. (See Example 2) Thus, changes to neighbor configuration options should be entered after putting the neighbor in a group.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures peer group "abc". Peers 1.2.3.4 and 4.3.2.1 are then added to this peer group.

(config)# router bgp 7345

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 4.3.2.1 remote-as 5

(config-router-bgp)# neighbor abc peer-group

(config-router-bgp)# neighbor 1.2.3.4 peer group abc

(config-router-bgp)# neighbor 4.3.2.1 peer-group abc

(config-router-bgp)# exit

(config)#

Example 2

The following example configures a peer group called xyz. Peer 10.133.10.23 is configured separately, then a route map named "import" is imported into that peer. The peer is then added to the peer group. The result of adding this neighbor to peer group xyz is that the route-map setting will be lost. This is because once you put a neighbor in a group, it loses all options previously configured on the neighbor except for its AS number.

(config)# router bgp 201

(config-router-bgp)# neighbor xyz peer-group

(config-router-bgp)# neighbor 10.133.10.23 remote-as 201

(config-router-bgp)# neighbor 10.133.10.23 route-map import in

(config-router-bgp)# neighbor 10.133.10.23 peer-group xyz

(config-router-bgp)# exit

(config)#

neighbor preference2

Name

neighbor preference2 - breaks a preference tie between two groups in a BGP peer

neighbor receive-buffer

Border Gateway Protocol (BGP) Page 131

Syntax

neighbor [ip_address | group-name] preference2 pref2

no neighbor [ip_address | group-name] preference2 pref2

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

pref2 - an integer between 0 and 255, inclusive

Description

The neighbor preference2 command breaks a preference tie between groups in a BGP peer.

Preferences are the first criteria of comparison for route selection. When a route has been learned from more than one protocol, the active route will be selected from the protocol with the lowest preference.

The negative form of this command, no preference2, removes the configured value and returns this to its

default value of 0.

Default

If neighbor preference2 is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] preference2 0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the global BGP preference2 value to be 20 and the BGP preference2 value for peer 1.2.3.4 to be 10.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# preference2 20

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 preference2 10

(config-router-bgp)# exit

(config)#

neighbor receive-buffer

Name

neighbor receive-buffer - controls the amount of memory requested from the kernel for the receive

buffer

Syntax

neighbor [ip_address | group-name] receive-buffer kbufsize

neighbor remote-as

Border Gateway Protocol (BGP) Page 132

no neighbor [ip_address | group-name] receive-buffer kbufsize

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

kbufsize - kernel send-buffer size in bytes, specified as an integer between 4096 and 4,294,967,295,

inclusive

Description

The neighbor receive-buffer command controls the amount of memory requested from the kernel for

the receive buffer. The maximum supported is 4,294,967,295 bytes; although many kernels have a lower limit. By default, Advanced Routing Suite configures the maximum supported. This command is not necessary on normally functioning systems.

Default

By default, Advanced Routing Suite configures the maximum supported. The maximum supported is 4,294,967,295 bytes; although many kernels have a lower limit.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example limits the receive buffer to 5000 bytes for this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 receive-buffer 5000

(config-router-bgp)# exit

(config)#

neighbor remote-as

Name

neighbor remote-as - configures the remote AS for an IPv4 peer

Syntax

neighbor ip_address remote-as as_num

no neighbor ip_address remote-as as_num

Mode

BGP Router Configuration

Parameters

ip_address - a valid IPv4 address specified in dotted-quad format

neighbor remove-private-as

Border Gateway Protocol (BGP) Page 133

remote-as as_num - the autonomous system (AS) number of a BGP peer. This can be an integer from 1

to 65535, inclusive.

Description

The neighbor remote-as command configures the IPv4 address of the host machine. You must specify

this command before configuring any other BGP peer commands.

Default

BGP peers are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a BGP peer with an IPv4 address of 1.2.3.4 and an AS number of 5.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# exit

(config)#

neighbor remove-private-as

Name

neighbor remove-private-as - specifies whether to remove private autonomous system (AS) numbers

from outbound updates to a peer or peer group

Syntax

neighbor [ip_address | group-name] remove-private-as

no neighbor [ip_address | group-name] remove-private-as

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use the neighbor remove-private-as command to remove private AS numbers when sending updates

to a peer or peer group.

Default

If neighbor remove-private-as is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] remove-private-as

neighbor route-map

Border Gateway Protocol (BGP) Page 134

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes BGP to strip private AS numbers from updates to this peer.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 remove-private-as

(config-router-bgp)# exit

(config)#

Example 2

The following example causes BGP to no longer remove private AS numbers.

(config)# router bgp 64512

(config-router-bgp)# no neighbor 1.2.3.4 remove-private-as

(config-router-bgp)# exit

(config)#

neighbor route-map

Name

neighbor route-map - specifies a route map for filtering routes to or from a BGP peer

Syntax

neighbor ip_address route-map rm-name [in | out]

no neighbor ip_address route-map rm-name [in | out]

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

rm-name - the name of a configured route map

in | out - specify whether the route map should be applied to routes being learned from (in) or sent to

(out) BGP

Description

Route maps are used to control the redistribution of routes between protocols. After configuring a route map,

it can then be specified in BGP. Use the neighbor route-map command to specify a configured route

map to be exported into or out of BGP.

Default

Route Maps are not explicitly specified by default.

neighbor route-reflector-client

Border Gateway Protocol (BGP) Page 135

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a configured route map named "abc" is specified to be exported into BGP.

(config)# router bgp 4444

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 route-map abc in

(config-router-bgp)# exit

neighbor route-reflector-client

Name

neighbor route-reflector-client - specifies that Advanced Routing Suite will act as a route

reflector for this neighbor

Syntax

neighbor [ ip_address | group-name ] route-reflector- client [meshed]?

no neighbor [ ip_address | group-name ] route-reflector- client [meshed]?

Mode

BGP Router Configuration

Address Family Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

meshed - optionally specify whether the reflector client is meshed

Description

The neighbor route-reflector-client command specifies that Advanced Routing Suite will act as a

route reflector for this group. Configuring the negative of this command specifies that Advanced Routing Suite will not act as an intra-group reflector and thus will not reflect routes back to peers within the same group. This is used when client peers within a route-reflection group are fully meshed.

Default

Route reflector clients are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that the neighbor 1.2.3.4 is to be a route reflector client.

(config)# router bgp 64512

neighbor route-to-peer

Border Gateway Protocol (BGP) Page 136

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 route-reflector-client

(config-router-bgp)# exit

(config)#

neighbor route-to-peer

Name

neighbor route-to-peer - specifies the actual time to live (TTL) used on a socket in all cases

Syntax

neighbor [ ip_address | group-name ] route-to-peer

no neighbor [ ip_address | group-name ]route-to-peer

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

The neighbor route-to-peer command specifies the actual TTL used on a socket in all cases. In

particular, if Advanced Routing Suite realizes that two BGP speakers are peering over a single network,

Advanced Routing Suite automatically sets the dontroute option on their peering session. This, in turn,

causes the TTL of the packets to be set to 1. The neighbor route-to-peer command prevents the

dontroute option from being set. If you specify route-to-peer, but do not specify a TTL, and you are

directly connected, then Advanced Routing Suite will set the TTL of your peering session to 1. If you want a

TTL greater than 1 for directly connected peers, you must specify both route-to-peer and the ttl_num

that you require. Refer to the "neighbor ttl" ("neighbor ttl" on page 140) command.

Default

If neighbor route-to-peer is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor ip_address route-to-peer

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables the route-to-peer option for this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 route-to-peer

(config-router-bgp)# exit

(config)#

neighbor send-buffer

Border Gateway Protocol (BGP) Page 137

neighbor send-buffer

Name

neighbor send-buffer - controls the amount of send buffering asked of the kernel

Syntax

neighbor [ip_address | group-name] send-buffer kbufsize

no neighbor [ip_address | group-name] send-buffer kbufsize

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

kbufsize - kernel send-buffer size in bytes, specified as an integer between 4096 and 4,294,967,295,

inclusive

Description

The neighbor send-buffer command controls the amount of memory requested from the kernel for the

send buffer. The maximum supported is 4,294,967,295 bytes; although many kernels have a lower limit. By default, Advanced Routing Suite configures the maximum supported. This command is not needed on normally functioning systems.

Default

By default, Advanced Routing Suite configures the maximum supported. The maximum supported is 4,294,967,295 bytes; although many kernels have a lower limit.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example limits the send buffer to 5000 bytes for this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 send-buffer 5000

(config-router-bgp)# exit

(config)#

neighbor send-community

Name

neighbor send-community - specifies whether communities are permitted to be sent

neighbor soft-reconfiguration inbound

Border Gateway Protocol (BGP) Page 138

Syntax

neighbor ip_address send-community

no neighbor ip_address send-community

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

Description

Use neighbor send-community to specify whether communities are permitted in a peer.

Default

If neighbor send-community is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor ip_address send-community

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes Advanced Routing Suite to send any specific community values to peer 1.2.3.4.

(config)# router bgp 60001

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 send-community

(config-router-bgp)# exit

(config)#

Example 2

The following example causes Advanced Routing Suite to not send any communities to this peer.

(config)# router bgp 60001

(config-router-bgp)# no neighbor 1.2.3.4 send-community

(config-router-bgp)# exit

(config)#

neighbor soft-reconfiguration inbound

Name

neighbor soft-reconfiguration inbound - activates the route refresh capability for a peer or peer

group

Syntax

neighbor [ip_address | group-name] soft-reconfiguration inbound

neighbor timers

Border Gateway Protocol (BGP) Page 139

no neighbor [ip_address | group-name] soft-reconfiguration inbound

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

Use the neighbor soft-reconfiguration inbound command to activate the route refresh capability

for this peer.

Default

If neighbor soft-reconfiguration inbound is not specified, it is the same as if the user had

specified the following:

(config-router-bgp)# no neighbor [ip_address |

group-name] soft-reconfiguration inbound

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns on the route refresh capability for peer 1.2.3.4.

(config)# router bgp 60101

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 soft-reconfiguration inbound

(config-router-bgp)# exit

(config)#

neighbor timers

Name

neighbor timers - specifies holdtime and keepalive time values within a BGP peer

Syntax

neighbor [ip_address | group-name] timers [ keepalive_value holdtime_value ]

no neighbor [ip_address | group-name] timers [ keepalive_value holdtime_value ]?

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

neighbor ttl

Border Gateway Protocol (BGP) Page 140

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

keepalive_value - the time, in seconds, between keepalive messages with a value range between 0

and 4,294,967,295, inclusive

holdtime_value - the time, in seconds of the BGP Hold Timer with a value of 0 or a value between 3 and

65535, inclusive

Description

The BGP keepalive timer will be set to one-third of the negotiated holdtime by default. Use keepalive to specify the number of seconds that will elapse between keepalive messages.

The holdtime value specifies the number of seconds to use when negotiating a peering session within this group. If Advanced Routing Suite does not receive a keepalive, update, or notification message within the specified period, then the BGP connection will be closed.

The negotiated holdtime value is the lesser of the values sent in the exchanged BGP Open messages. If a time of zero is specified, no keepalives will be sent. If a time of zero is received from the remote peer, then the holdtime must be configured to be zero in order for the peering session to become established.

Note: You cannot specify a holdtime value of 1 or 2. Attempting to do so will result in an error.

The negative form of this command, no neighbor timers, removes the configured values and returns this

to its default values of 180 and 60 seconds, respectively. Note: Specifying a value for holdtime and

keepalive in the no form of this command has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If neighbor timers is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] timers 180 60

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a keepalive value of 40 seconds and a holdtime value of 90 seconds for this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 timers 40 90

(config-router-bgp)# exit

(config)#

neighbor ttl

Name

neighbor ttl - specifies time to live (TTL) value

Syntax

neighbor [ip_address | group-name] ttl ttl_num

no neighbor [ip_address | group-name] ttl ttl_num

neighbor update-source

Border Gateway Protocol (BGP) Page 141

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

ttl_num - an integer from 1 to 255 specifying either a number of seconds or a number of hops

Description

The neighbor ttl command is provided mainly for attempting to communicate with improperly functioning

routers that ignore packets sent with a TTL value of 1. The ttl_num value has two units: seconds and number of hops. Either of these can be used. Note: Not all kernels allow the TTL to be specified for TCP connections.

Default

By default, Advanced Routing Suite sets the IP TTL for local peers to 1 and the TTL for non-local peers to the default kernel value.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a TTL value of 5 for this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 ttl 5

(config-router-bgp)# exit

(config)#

neighbor update-source

Name

neighbor update-source - specifies the IP address to be used on the local end of the TCP connection

with the peer

Syntax

neighbor [ip_address | group-name] update-source source_addr

no neighbor [ip_address | group-name] update-source source-addr

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

neighbor use-med

Border Gateway Protocol (BGP) Page 142

source-addr - the local IP interface address

Description

Use neighbor update-source to specify the IP address to be used on the local end of the TCP

connection with the peer. This is the address of a broadcast, NBMA or loopback interface and the local address of a point-to-point interface.

For external peers, the local address must be on an interface that is shared with the peer or with the peer’s gateway when a gateway is used. A session with an external peer will be opened only when an interface with the appropriate local address (through which the peer or gateway address is directly reachable) is operating. For internal peers, a peer session will be maintained when any interface with the specified local address is operating. In any case, an incoming connection will be recognized as a match for a configured peer only if it is addressed to the configured local address.

Default

The default update-source address is the IP address of a shared interface.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes the TCP session to peer 1.2.3.4 to be established over the interface 4.3.2.1.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 update-source 4.3.2.1

(config-router-bgp)# exit

(config)#

Example 2

The following example causes the TCP session to be established over the shared interface.

(config)# router bgp 65535

(config-router-bgp)# no neighbor 1.2.3.4 update-source 4.3.2.1

(config-router-bgp)# exit

(config)#

neighbor use-med

Name

neighbor use-med - specifies whether MEDs will be used in routing computations

Syntax

neighbor [ip_address | group-name] use-med

no neighbor [ip_address | group-name] use-med

Mode

BGP Router Configuration

neighbor v4-gateway

Border Gateway Protocol (BGP) Page 143

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

Description

By default, any MED (Multi_Exit_Disc) received on a BGP connection is ignored. If MEDs are to be

used in selecting routes, the use-med option must be specified. When two routes to the same destination

are received from different peers within the same peer-as, they could have different MEDs. When choosing between these routes, assuming that nothing else makes one preferable to the other (such as configured policy), the values of the differing MEDs are used to choose which route to use. In this comparison, the route with the lowest MED is preferred. Routes without MEDs are treated as having a MED value of zero unless "bgp bestpath med missing-as-worst" ("bgp bestpath med missing-as-worst" on page 82) is configured on.

Default

If neighbor use-med is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# no neighbor [ip_address | group-name] use-med

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example causes BGP to pay attention to MED values received from this peer.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 use-med

(config-router-bgp)# exit

(config)#

Example 2

The following example causes BGP to ignore MED values received from this peer.

(config)# router bgp 65535

(config-router-bgp)# no neighbor 1.2.3.4 use-med

(config-router-bgp)# exit

(config)#

neighbor v4-gateway

Name

neighbor v4-gateway - configures an IPv4 intermediate destination by which packets are delivered to

their ultimate destination

Syntax

neighbor [ip_address | group-name] v4-gateway gwv4_address

neighbor version

Border Gateway Protocol (BGP) Page 144

no neighbor [ip_address | group-name] v4-gateway gwv4_address

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

gwv4_address - the IPv4 address of the gateway specified in dotted-quad format

Description

A gateway is an intermediate destination by which packets are delivered to their ultimate destination. This command instructs Advanced Routing Suite to use a form of multi-hop EBGP.

If a network is not shared with this group, then this command specifies a router on an attached network to be used as the next hop router for routes received from this peer.

The gateway can also be used to specify a next hop for groups that are on shared networks. For example, you might use gateway to ensure that third-party next hops are never accepted from a given group by specifying that group’s address as its own gateway. The gateway specified must have consistent routing information to prevent routing loops. In most cases, the gateway is not needed.

Default

The neighbor v4-gateway command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures address 192.168.1.1 as a gateway address for peer 1.1.1.1.

(config)# router bgp 64512

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# neighbor 1.1.1.1 remote-as 5

(config-router-bgp)# neighbor 1.1.1.1 v4-gateway 192.168.1.1

(config-router-bgp)# exit

(config)#

neighbor version

Name

neighbor version - specifies the BGP version number to use

Syntax

neighbor [ip_address | group-name] version num

Mode

BGP Router Configuration

Parameters

ip_address - the IP address of a BGP peer specified as a valid IPv4 address in dotted-quad format

network

Border Gateway Protocol (BGP) Page 145

group-name - the name of a BGP peer group specified as a string of characters. Note: If an invalid IP

address is specified (for example 256.1.1.1), it will be read as a group name.

num - the BGP version number. Currently, this can only be 4.

Description

User neighbor version to specify the version of BGP you want to run on a peer group or peer. Because

only version 4 is currently supported, there is no negative form of this command available.

Default

If neighbor version is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# neighbor [ip_address | group-name] version 4

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures BGP version 4 on peer 1.2.3.4.

(config)# router bgp 65534

(config-router-bgp)# bgp router-id 1.1.1.1

(config-router-bgp)# neighbor 1.2.3.4 remote-as 5

(config-router-bgp)# neighbor 1.2.3.4 version 4

(config-router-bgp)# exit

network

Name

network - specifies prefixes to be imported into BGP

Syntax

network (ipv4_address (mask net-mask))[route-map name]? [restrict]?

no network (ipv4_address (mask net-mask))[route-map name]? [restrict]?

Mode

BGP Router Configuration

Address Family Mode

Parameters

ipv4_address (mask net-mask) - specify an IPv4 address with an optional mask value. The

ipv4_address and net-mask values are specified in dotted-quad format

route-map name - optionally specify a route map to apply policy to the prefix

restrict - optionally specify that the matching network range should not be advertised to other peers

Description

The network command is used to specify prefixes that should be imported into BGP. The negative form of

this command removes configured network prefixes.

Note: Some competitors set the BGP ORIGIN attribute differently on routes configured via the static statement (origin incomplete) than via the BGP network statement (origin IGP). Advanced Routing Suite always sets origin incomplete. Use the "set origin" Route Map command to modify the origin.

preference2

Border Gateway Protocol (BGP) Page 146

Default

Network prefixes are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example imports the network 10.1.0.0 with a mask of 255.255.255.0 into BGP. Additionally, this network range will be advertised to other peers.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# network 10.1.0.0 mask 255.255.255.0 permit

(config-router-bgp)# exit

(config)#

See Also

Chapter 31 Route Maps

preference2

Name

preference2 - breaks a preference tie between two groups

Syntax

preference2 pref2

no preference2 pref2?

Mode

BGP Router Configuration

Parameters

pref2 - an integer between 0 and 255, inclusive

Description

The preference2 command breaks a preference tie between groups. Preferences are the first criteria of

comparison for route selection. When a route has been learned from more than one group, the active route will be selected from the group with the lowest preference.

The negative form of this command, no preference2, removes the configured value and returns this to its

default value of 0. Note: Specifying a value for pref2 in the no form has no effect on the configuration. Thus,

it is displayed above as optional.

Default

If preference2 is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# preference2 0

Command History

NGC 2.2 - This command was introduced.

redistribute

Border Gateway Protocol (BGP) Page 147

Examples

Example 1

The following example configures the global BGP preference2 value to be 20.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# preference2 20

(config-router-bgp)# exit

(config)#

Example 2

The following example removes the configured BGP preference2 value and reverts it back to its default value.

(config)# router bgp 65535

(config-router-bgp)# no preference2 20

(config-router-bgp)# exit

(config)#

redistribute

Name

redistribute - specifies routes to export to the current protocol

Syntax

redistribute protocol [route-map name]? {0,10}

no redistribute protocol [route-map name]?

Mode

BGP Router Configuration

Parameters

protocol - the protocol name whose routes you want to redistribute to the current protocol being

configured. Valid protocols are aggregate, bgp, isis, kernel, ospf, ospf-ase, rip, ripng, and static.

route-map name - the name of a route map to apply to these routes. Specifying this is optional.

{0,10} - although this command can be given multiple times, it can only be given once for each of the

configurable protocols. In other words, if a redistribute command is given for a protocol and route map,

and then given again for the same protocol with a different route map, the second configuration overrides the first.

Description

Use the redistribute command to specify routes to export into the BGP. This command causes routes

from the specified protocol to be considered for redistribution into BGP. Additionally, if a route map is specified, then routes from the specified protocol that match the named route map will be considered for redistribution into the current protocol. If the referenced route map has not yet been configured, then an empty route map is created with the specified name.

Note: Configuring this away from its default removes the implicitly configured default. You will have to go

back and specify to redistribute BGP routes after the first redistribute configuration in order to export

those routes.

redistribute

Border Gateway Protocol (BGP) Page 148

Default

The default is to export BGP routes. Note that this is an implicit default that is wiped away with the first redistribute configuration.

Example

Example 1

In the following example BGP is configured to redistribute all RIP and RIPng routes.

(config)# router bgp 65535

(config-router-bgp)# redistribute rip

(config-router-bgp)# redistribute ripng

(config-router-bgp)# exit

(config)#

Example 2

In the following example, the route map set med is applied to OSPF routes and exported into BGP.

(config)# route map setmed

(config-route-map)# set med 20

(config-route-map)# exit

(config)# router bgp

(config-router-bgp)# redistribute ospf route-map setmed

(config-router-bgp)# exit

(config)#

Example 3

In the following example, route map "abc" is configured with the following match criteria:

If a route matches interface "fxp1", then communities specified in community "com-set-1" will be added to the route and the metric of the route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# set community-set com-set-1

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

This route map is then applied to static routes and exported into BGP.

(config)# router bgp 65121

(config-router-bgp)# redistribute static route-map abc

(config-router-bgp)# exit

See Also

"distribute-list" ("distribute-list" on page 96)

router bgp

Border Gateway Protocol (BGP) Page 149

router bgp

Name

router bgp - configures BGP on a router and specifies the router’s autonomous system number

Syntax

router bgp as_number

no router bgp as_number

Mode

Global Configuration

Parameters

as_number - an integer between 1 and 65535, inclusive

Description

The router bgp command enables BGP on a router. Because there is no default as_number, an

autonomous system number must also be specified. The negative form of this command, no router bgp,

disables BGP on a router.

Default

BGP is disabled by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the router to be a BGP speaker in AS number 65535.

(config)# router bgp 65535

(config-router-bgp)#

Example 2

The following example turns off BGP on the router.

(config)# no router bgp 65535

(config)#

show ip bgp

Name

show ip bgp - displays information about BGP routes installed in the BGP routing information base (RIB)

Syntax

show ip bgp [ip_address]? [prefix (longer-prefixes?)]

Mode

User Execution

show ip bgp instance

Border Gateway Protocol (BGP) Page 150

Parameters

ip_address - optionally specify an IP address

prefix - optionally specify a prefix with an address and a mask length

longer-prefixes - if a prefix is specified, optionally specify to show routes matching the specified

Network/Mask pair only

Description

Use the show ip bgp query to obtain information about BGP routes installed in the BGP RIB.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns BGP information for all BGP routes installed in the BGP RIB.

> show ip bgp

Network Next Hop R Metric LocPref Path 1.2.3.4/24 192.165.251.1 u 9 100 201 202

1.2.3.5/24 192.165.251.1 u 10 100 201 202

Field Descriptions

The following table describes the fields that appear in the BGP Query.

Table 13-1 BGP Query Fields

Field Description

Network The value of a BGP route

Next Hop The Next Hop address corresponding to the BGP route

R Specifies whether the route is installed in the unicast or multicast RIB

Metric The MED value for the route

LocPref The Local Preference value for the route

Path The route’s AS Path

show ip bgp instance

Name

show ip bgp instance - shows current BGP instance information

Syntax

show ip bgp instance

show ip bgp neighbors

Border Gateway Protocol (BGP) Page 151

Mode

User Execution

Parameters

none

Description

Use the show ip bgp instance query to obtain summarized information about the current BGP instance.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows information about the current BGP instance.

> show ip bgp instance

Instance ID is 0

show ip bgp neighbors

Name

show ip bgp neighbors - displays information about the state of BGP’s IPv4 peering sessions

Syntax

show ip bgp neighbors [ipv4-address]?

Mode

Privileged Execution

Parameters

ipv4-address - optionally enter an IPv4 address to view information for only the specified neighbor

Description

Use the show ip bgp neighbors query to obtain detailed information about the state of BGP’s peering

sessions. You can optionally specify an IPv4 address. When you do so, the output of the query will display information for the specified address.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows detailed information about all BGP peering sessions.

# show ip bgp neighbors

BGP neighbor is 10.11.31.32, remote AS 65534 BGP version is 4, remote router ID 10.133.10.32 Negotiated version is 4 TTL is 0 holdtime is 180 restart-time is 0 Restarting: no Current state is "Established"

show ip bgp orf

Border Gateway Protocol (BGP) Page 152

Last state was "OpenConfirm" Last event was "RecvKeepAlive" Last error code was 0 Last error subcode was 0 Local address is 10.11.31.31 Local AS is 65535 Local router ID is 192.168.11.31 Capabilities: Multicprotocol IPv4 Unicast: no Graceful Restart IPv4 Unicast: no Multiprotocol IPv4 Multicast: no Graceful Restart IPv4 Multicast: no Route Refresh: no Send End-of-RIB messages: no Dynamic Capabilities: no

BGP neighbor is 10.11.31.33, remote AS 65533 BGP version is 4, remote router ID 192.168.11.33 Negotiated version is 4 TTL is 0 holdtime is 180 restart-time is 0 Restarting: no Current state is "Established" Last state was "OpenConfirm" Last event was "RecvKeepAlive" Last error code was 0 Last error subcode was 0 Local address is 10.11.31.31 Local AS is 65535 Local router ID is 192.168.11.31 Capabilities: Multiprotocol IPv4 Unicast: no Graceful Restart IPv4 Unicast: no Multiprotocol IPv4 Multicast: no Graceful Restart IPv4 Multicast: no Route Refresh: no Send End-of-RIB messages: no Dynamic Capabilities: no

show ip bgp orf

Name

show ip bgp orf - displays ORF-related information for all peers or for a specific peer

Syntax

show ip bgp orf ip_address?

Mode

User Execution

Parameters

ip_address - optionally specify the IPv4 address of a peer for which you want ORF information returned

Description

Use the show ip bgp orf query to view ORF-related information for a single peer or for all peers.

show ip bgp paths

Border Gateway Protocol (BGP) Page 153

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

In the following example, ORF information for all peers is displayed.

> show ip bgp orf

ORFs for peer 1.2.3.4 prefix 10.0.0.0/8 ge 8 le 8 deny community 200:300 extcommunity rt 192.168.10.2:500 ORFs for peer 2.2.2.2 community 202:302 community 400:500

Example 2

In the following example, ORF information is returned for peer 2.2.2.2 only.

> show ip bgp orf 2.2.2.2

ORFs for peer 2.2.2.2 community 202:302 community 400:500

Field Descriptions

The following table describes the fields that appear in the BGP ORF Query.

Table 13-1 BGP ORF Query Fields

Field Description

ORFs for peer The IPv4 address of the BGP peer

prefix Prefix filter information, including the prefix, mask, permit or deny, and the range

community The community filter

extcommunity The extended community filter

show ip bgp paths

Name

show ip bgp paths - displays BGP AS Path information

Syntax

show ip bgp paths

show ip bgp peer-group

Border Gateway Protocol (BGP) Page 154

Mode

User Execution

Privileged Execution

Parameters

none

Description

Use the show ip bgp paths query to view AS Path information.

Command History

NGC 2.3 - This command was introduced.

Examples

The following example is a query for AS Paths.

> show ip bgp paths

Refcount Metric Path 5 0 IGP (Id 2) 12 0 Incomplete (Id 1)

show ip bgp peer-group

Name

show ip bgp peer-group - displays information about BGP peer groups

Syntax

show ip bgp peer-group [name]?

Mode

User Execution

Parameters

name - optionally specify the name of a peer group

Description

Use the show ip bgp peer-group query to obtain BGP peer group information. If a name is not specified,

then information about all BGP peer groups is displayed.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns information for all BGP peer groups.

> show ip bgp peer-group

BGP peer-group is abc BGP version 4 For address family: IPv4 Unicast BGP neighbor is abc, peer-group external, members: 192.168.100.1 192.168.100.2

show ip bgp summary

Border Gateway Protocol (BGP) Page 155

Field Descriptions

The following table describes the fields that appear in the BGP Peer Group Query.

Table 13-1 BGP Peer Group Query Fields

Field Description

Version The version of BGP that this group is using

peer-group external/internal The type of this peer group

members: List of IP addresses of peers that belong to this group

show ip bgp summary

Name

show ip bgp summary - shows summarized BGP information

Syntax

show ip bgp summary

Mode

User Execution

Parameters

none

Description

Use the show ip bgp summary command to view summarized BGP information, including the router ID and

the local AS number.

Command History

NGC 2.2 - This command was introduced

Examples

The following example shows a request for summarized BGP information.

> show ip bgp summary

BGP router identifier 65.247.36.97, local AS number 4

>

timers bgp

Name

timers bgp - specifies global keepalive and holdtime values for BGP

timers bgp

Border Gateway Protocol (BGP) Page 156

Syntax

timers bgp keepalive_value holdtime_value

no timers bgp [keepalive_value holdtime_value]?

Mode

BGP Router Configuration

Parameters

keepalive_value - the time, in seconds, between keepalive messages with a value range between 0

and 4,294,967,295, inclusive

holdtime_value - the time, in seconds of the BGP Hold Timer with a value of 0 or a value between 3 and

65535, inclusive

Description

The BGP keepalive timer will be set to one-third of the negotiated holdtime by default. The keepalive value specifies the number of seconds that will elapse between keepalive messages.

The holdtime value specifies the number of seconds to use when negotiating a peering session. If Advanced Routing Suite does not receive a keepalive, update, or notification message within the specified period, then the BGP connection will be closed. The negotiated holdtime value is the lesser of the values sent in the exchanged BGP Open messages. If a time of zero is specified, no keepalives will be sent. If a time of zero is received from the remote peer, then the holdtime must be configured to be zero in order for the peering session to become established.

Note: You cannot specify a holdtime value of 1 or 2. The value can be 0 or at least 3.

The negative form of this command, no timers bgp, removes the configured values and returns this to its

default values of 180 and 60 seconds, respectively. Note: Specifying a value for keepalive and holdtime in

the no form of this command has no effect on the configuration. Thus, it is displayed above as optional.

Default

If timers bgp is not specified, it is the same as if the user had specified the following:

(config-router-bgp)# timers bgp 180 60

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example sets the BGP keepalive value to 30 seconds and the holdtime value to 90 seconds. Notice that the values have positional significance. The keepalive value must appear first, and the holdtime value must appear second.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# timers bgp 30 90

(config-router-bgp)# exit

(config)#

Example 2

The following example removes the user-configured timer values and returns these to their defaults.

(config)# router bgp 65535

(config-router-bgp)# no timers bgp

(config-router-bgp)# exit

trace file

Border Gateway Protocol (BGP) Page 157

(config)#

trace file

Name

trace file - specifies the file to receive tracing information, the size of the file, whether to overwrite

existing files, and the maximum number of files allowed

Syntax

trace file file_name [no-timestamp || overwrite]?

no trace file file_name [no-timestamp || overwrite]?

Mode

BGP Router Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For BGP, the trace file command in BGP Router Configuration

Mode specifies a file for tracing of all BGP events. The negative form of this command disables this tracing.

The specific events that are traced are controlled by the trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config-router-bgp)# trace file /var/log/bgp.log no-timestamp

(config-router-bgp)# trace file /var/log/bgp.log max-files 10

The option given in the second command completely replaces that given in the first. In order to specify both

no-timestamp and max-files 10, they must be entered on the same line as follows.

(config-router-bgp)# trace file /var/log/bgp.log max-files 10 no-timestamp

Default

BGP tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, BGP tracing is written to the file "/var/tmp/bgp.log". No timestamp will display at the beginning of the trace lines.

(config)# router bgp 65535

(config-router-bgp)# bgp router-id 1.2.3.4

trace flag

Border Gateway Protocol (BGP) Page 158

(config-router-bgp)# trace file /var/tmp/bgp.log no-timestamp

trace flag

Name

trace flag - specifies BGP-specific tracing options as well as options that are common across all

protocols

Syntax

trace flag ( [ route | normal | state | policy | task | timer | all | aspath ]) | ( [ packets | open | update | keepalive | notify ] [ send | receive | send-receive ]? [detail?] )

no trace flag ( [ route | normal | state | policy | task | timer | all | aspath ]) | ( [ packets | open | update | keepalive | notify ] [ send | receive | send-receive ]? [detail?] )

Mode

BGP Router Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags. Note: When issuing a show command, the output will display all the trace

flags rather than this all keyword.

GP-specific flags that do not allow associated actions:

[ aspath ] - The following BGP-specific flags cannot be associated with the send, receive,

send-receive, and detail action items. These flags are defined as follows:

aspath - traces AS Path messages

GP-specific flags that allow associated actions:

[ packets | open | update | keepalive | notify ] - The following BGP-specific flags can

be associated with the send, receive, send-receive, and detail action items. These flags are defined as follows:

packets - trace all BGP packets

open - trace BGP Open packets

update - trace BGP Update packets

keepalive - trace BGP Keepalive packets

trace flag

Border Gateway Protocol (BGP) Page 159

notify - trace BGP Notification messages

[ send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets

sent, received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the trace flag command to specify tracing flags for BGP tracing. Each flag must reside on its own

configuration line. For example, you cannot specify to trace both open and keepalive packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received update and keepalive messages are traced in detail. This tracing information will be written to the file /var/tmp/bgp.log.

(config)# router bgp 65525

(config-router-bgp)# bgp router-id 1.2.3.4

(config-router-bgp)# trace file /var/tmp/bgp.log

(config-router-bgp)# trace flag update send-receive detail

(config-router-bgp)# trace flag keepalive send-receive detail

(config-router-bgp)# exit

(config)#

Page 160

Chapter 9

Internet Control Message Protocol (ICMP)

In This Chapter

Internet Control Message Protocol (ICMP) Overview 160

router icmp 160

trace file 161

trace flag 162

Internet Control Message Protocol (ICMP) Overview

On systems without the BSD routing socket, Advanced Routing Suite listens to ICMP messages received by the system. Advanced Routing Suite currently supports redirect. Processing of ICMP redirect messages is handled by the "router redirect" command. See "Redirect Processing" for more information.

Currently, the only reason to enter ICMP Router Configuration mode is to be able to trace the ICMP messages that Advanced Routing Suite receives. These messages can be traced to a separate log file as is

allowed by any Advanced Routing Suite trace file command. This allows for easy separation of

non-redirect ICMP messages from redirect messages in the trace file.

router icmp

Name

router icmp - allows the user to enter ICMP Router Configuration Mode

Syntax

router icmp

Mode

Global Configuration

Parameters

none

Description

The router icmp command allows you to enter ICMP Router Configuration mode, where, currently only

tracing options are supported.

Note: Because ICMP is always on, a negative form of this command is not available. Type exit at the

(config-icmp)# prompt to leave ICMP Router Configuration mode.

trace file

Internet Control Message Protocol (ICMP) Page 161

Default

none

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows how to enter and exit ICMP Router Configuration mode on this router.

(config)# router icmp

(config-icmp)# exit

(config)#

trace file

Name

trace file - specifies file options during tracing for the ICMP protocol

Syntax

trace file file_name [|| no-timestamp || overwrite]?

no trace file file_name [ no-timestamp || overwrite]?

Mode

ICMP Router Configuration Mode

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For ICMP, the trace file command in ICMP Router Configuration

Mode specifies a file for tracing of all ICMP events. The negative form of this command disables this tracing.

The specific events that are traced are controlled by the trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config-icmp)# trace file /var/log/icmp.log no-timestamp

(config-icmp)# trace file /var/log/icmp.log

The option given in the second command completely replaces that given in the first.

Default

ICMP tracing is turned off by default.

trace flag

Internet Control Message Protocol (ICMP) Page 162

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, ICMP tracing is written to the file "/var/tmp/icmp.log". No timestamp will display at the beginning of the trace lines.

(config)# router icmp

(config-icmp)# trace file /var/tmp/icmp.log no-timestamp

trace flag

Name

trace flag - specifies additional tracing flags for ICMP tracing

Syntax

trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packet | redirect | router-discovery | info | error ] [ send | receive | send-receive ]? [detail?] )

no trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packet | redirect | router-discovery | info | error ] [ send | receive | send-receive ]? [detail?] )

Mode

ICMP Router Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

ICMP-specific flags:

[ packet | redirect | router-discovery | info | error ] - These ICMP-specific flags

can be associated with the send, receive, or send-receive action items. These flags are defined as follows:

packets - trace all ICMP packet types

redirect - trace only ICMP redirect packets

router-discovery - trace only ICMP router discovery packets

trace flag

Internet Control Message Protocol (ICMP) Page 163

info - trace only ICMP informational packets, which include mask request/response, info

request/response, echo request/response, and time stamp request/response

error - trace only ICMP error packets, which include time exceeded, parameter problem, unreachable,

and source quench

[ send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets

sent, received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the trace flag command to specify tracing flags for ICMP tracing. Each flag must reside on its own

configuration line. For example, you cannot specify to trace both redirect and info packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received request and response messages are traced in detail. This tracing information will be written to the file /var/tmp/icmp.log.

(config)# router icmp

(config-icmp)# trace file /var/tmp/icmp.log

(config-icmp)# trace flag request send-receive detail

(config-icmp)# trace flag response send-receive detail

See Also

Chapter 9 "Trace Options"

Page 164

Chapter 10

Fast Open Shortest Path First (OSPF)

In This Chapter

Fast Open Shortest Path First (OSPF) Overview 166

router ospf 170

advertise-subnet 171

authentication 172

compatible rfc1583 174

dead-interval 174

distance 175

enable 176

enable-te 177

hello-interval 178

igp-shortcut 179

inherit-metric 180

monitor-auth-key 180

multicast-rib 181

network area 182

nssa-inherit-metric 183

nssa-stability-interval 184

poll-interval 184

priority 185

redistribute 186

redistribute-nssa 188

require-vbit 189

restart-allow-changes 190

restart-enable 191

restart-max-sync-time 192

restart-type 193

retransmit-interval 193

router-id 194

timers spf 195

trace file 196

trace flag 197

transmit-delay 198

area advertise-subnet 199

area authentication 200

area dead-interval 202

area filter 203

area hello-interval 204

area nssa 205

area nssa-range 206

area nssa-translate-always 207

area poll-interval 208

trace flag

Fast Open Shortest Path First (OSPF) Page 165

area priority 209

area range 210

area retransmit-interval 211

area stub 212

area stubhost 213

area stubnetwork 214

area transmit-delay 215

area virtual-link 216

default-metric 217

default-nssa-metric 218

default-nssa-type 219

default-preference 219

default-tag 220

default-type 221

advertise-subnet 222

allow-all 223

authentication 223

cost 225

dead-interval 226

enable 227

hello-interval 228

neighbor 229

network 230

no-multicast 231

passive-interface 232

poll-interval 233

priority 234

retransmit-interval 235

traffic-eng administrative-weight 236

traffic-eng attribute-flags 237

traffic-eng bandwidth 238

transmit-delay 239

ip ospf advertise-subnet 240

ip ospf allow-all 241

ip ospf area 241

ip ospf authentication 242

ip ospf cost 244

ip ospf dead-interval 245

ip ospf enable 246

ip ospf hello-interval 247

ip ospf neighbor 248

ip ospf network 248

ip ospf no-multicast 249

ip ospf passive-interface 250

ip ospf poll-interval 251

ip ospf priority 252

ip ospf retransmit-interval 253

ip ospf traffic-eng administrative-weight 254

ip ospf traffic-eng attribute-flags 255

ip ospf traffic-eng bandwidth 256

ip ospf transmit-delay 256

Fast Open Shortest Path First (OSPF) Overview

Fast Open Shortest Path First (OSPF) Page 166

show ip ospf 257

show ip ospf border-routers 258

show ip ospf database 259

show ip ospf interface 260

show ip ospf neighbor 260

show ip ospf request-list 261

show ip ospf retransmission-list 262

show ip ospf summary-address 263

show ip ospf virtual-links 263

Fast Open Shortest Path First (OSPF) Overview

Open Shortest Path First Routing (OSPF) is a shortest path first or link-state protocol. OSPF is an interior gateway protocol that distributes routing information between routers in a single autonomous system (AS). OSPF chooses the least-cost path as the best path. OSPF is suitable for complex networks with a large number of routers because it provides equal-cost multi-path routing, where packets to a single destination can be sent via more than one interface simultaneously.

In a link-state protocol, each router maintains a database describing the entire AS topology, which it builds out of the collected link state advertisements of all routers. Each participating router distributes its local state (i.e., the router’s usable interfaces and reachable neighbors) throughout the AS by flooding. Each multi-access network that has at least two attached routers has a designated router and a backup designated router. The designated router floods a link state advertisement for the multi-access network and has other special responsibilities. The designated router concept reduces the number of adjacencies required on a multi-access network.

OSPF allows networks to be grouped into areas. Routing information passed between areas is abstracted, potentially allowing a significant reduction in routing traffic. OSPF uses the following four different types of routes, listed in order of preference: intra-area, inter-area, type 1 Autonomous System External (ASE), and type 2 ASE. Intra-area paths have destinations within the same area. Inter-area paths have destinations in other OSPF areas. Both types of ASE routes are routes to destinations external to OSPF (and usually external to the AS). Routes exported into OSPF ASE as type 1 ASE routes are supposed to be from interior gateway protocols (such as RIP) whose external metrics are directly comparable to OSPF metrics. When a routing decision is being made, OSPF will add the internal cost to the AS border router to the external metric. Type 2 ASEs are used for exterior gateway protocols whose metrics are not comparable to OSPF metrics. In this case, only the internal OSPF cost to the AS border router is used in the routing decision.

Note: It is possible to export a route into OSPFASE that has a nexthop inside an NSSA and not export that route into OSFPNSSA. A type 7 route (OSPFNSSA) should be originated in addition to the type 5 route (OSPFASE) in this case. To configure this, first do not originate a type 5 with a nexthop inside an NSSA. Second, originate all such routes into both OSPFASE and OSPFNSSA.

From the topology database, each router constructs a tree of the shortest paths, with itself as the root. This shortest-path tree gives the route to each destination in the AS. Externally-derived routing information appears on the tree as leaves. The link-state advertisement format distinguishes between information acquired from external sources and information acquired from internal routers, so there is no ambiguity about the source or reliability of routes. Externally-derived routing information (for example, routes learned from BGP) is passed transparently through the AS and is kept separate from OSPF’s internally derived data. Each external route can also be tagged by the advertising router, enabling routers on the borders of the AS to pass additional information between them.

OSPF optionally includes Type of Service (TOS) routing and allows administrators to install multiple routes to a given destination for each type of services, such as low delay or high throughput. A router running OSPF uses the destination address and the type of service to choose the best route to the destination.

OSPF intra- and inter-area routes are always imported into the Advanced Routing Suite routing database with a preference (or distance) of 10. Because it would violate the protocol if an OSPF router did not participate fully in the area’s OSPF, it is not possible to override this preference. Although it is possible to give other routes better preference values explicitly, doing so would violate the OSPF protocol and could

Fast Open Shortest Path First (OSPF) Overview

Fast Open Shortest Path First (OSPF) Page 167

lead to incorrect routing. Therefore, the only types of policy supported in OSPF are ASE import and ASE and NSSA export.

Hardware multicast capabilities are also used where possible to deliver link-status messages. OSPF areas

are connected by the backbone area, the area with identifier 0.0.0.0. All areas must be logically

contiguous, and the backbone is no exception. To permit maximum flexibility, OSPF allows the configuration of virtual links, which enables the backbone area to appear contiguous despite the physical reality.

Because a separate copy of the link-state algorithm is run for each area, most configuration parameters are defined on a per-area basis. All routers in an area must agree on that area’s parameters. Misconfiguration will keep neighbors from forming adjacencies between themselves, and routing information might not flow or could loop.

Advanced Routing Suite can run over a variety of physical connections: serial connections, LAN interfaces, ATM, or FDDI. The OSPF configuration supports three different types of connections in the interface clauses:

LAN and Point-to-Point

An example of a LAN interface is an Ethernet or a FDDI interface. A point-to-point interface can be a serial line using Point-to-Point protocol. Advanced Routing Suite will use a Multicast IP address on LAN interfaces to reach OSPF routers.

Non-Broadcast Multiple Access

ATM with virtual circuits is an example of a Non-Broadcast Multiple Access medium. Because there is no general multicast in all ATM devices, each router must be listed so that Advanced Routing Suite can poll each router. Advanced Routing Suite will unicast the packets to the routers in the NBMA network.

Point-to-Multipoint

Point-to-Multipoint connectivity is used when the network does not provide full connectivity to all routers in the network. Just as on the NBMA format, you must provide a list of routers that the Advanced Routing Suite daemon will query as OSPF peers.

Notes:

It is suggested that users of OSPF configure interface parameters using a physical interface name (for example, "fxp0"). This provides the clearest, least ambiguous way of configuring these parameters. Using a logical address (for example, "192.168.10.1") can lead to undesirable results.

If the same interface is configured in two different areas, the interface will run on the numerically lowest area address.

Floating interfaces are those that are configured independently of an area and, thus, can "float" between areas. Conflicting configurations can occur between Area interface commands and Floating interface commands. For example, a user can configure the Hello interval to be 1 for an interface through the Floating interface command or to be 2 for that same interface through the Area interface command. In such a case, the Area interface command configuration is selected.

OSPF Commands

Global Configuration Mode OSPF Commands

The following command is configured in Global Configuration Mode:

"router ospf" ("router ospf" on page 170)

Global Commands

The following are OSPF global-wide commands that are configured in OSPF Router Configuration Mode:

"advertise-subnet" ("advertise-subnet" on page 171)

"authentication" ("authentication" on page 172)

"compatible rfc1583" ("compatible rfc1583" on page 174)

"dead-interval" ("dead-interval" on page 174)

"distance" ("distance" on page 175)

Fast Open Shortest Path First (OSPF) Overview

Fast Open Shortest Path First (OSPF) Page 168

"enable" ("enable" on page 176)

"enable-te" ("enable-te" on page 177)

"hello-interval" ("hello-interval" on page 178)

"igp-shortcut" ("igp-shortcut" on page 179)

"inherit-metric" ("inherit-metric" on page 180)

"monitor-auth-key" ("monitor-auth-key" on page 180)

"multicast-rib" ("multicast-rib" on page 181)

"network area" ("network area" on page 182)

"nssa-inherit-metric" ("nssa-inherit-metric" on page 183)

"nssa-stability-interval" ("nssa-stability-interval" on page 184)

"poll-interval" ("poll-interval" on page 184)

"priority" ("priority" on page 185)

"redistribute" ("redistribute" on page 186)

"redistribute-nssa" ("redistribute-nssa" on page 188)

"require-vbit" ("require-vbit" on page 189)

"restart-allow-changes" ("restart-allow-changes" on page 190)

"restart-enable" ("restart-enable" on page 191)

"restart-max-sync-time" ("restart-max-sync-time" on page 192)

"restart-type" ("restart-type" on page 193)

"retransmit-interval" ("retransmit-interval" on page 193)

"router-id" ("router-id" on page 194)

"timers spf" ("timers spf" on page 195)

"trace file" ("trace file" on page 196)

"trace flag" ("trace flag" on page 197)

"transmit-delay" ("transmit-delay" on page 198)

Area Commands

The following are OSPF area-wide commands that are configured in OSPF Router Configuration Mode. These configurations override any similar global-wide commands:

"area advertise-subnet" ("area advertise-subnet" on page 199)

"area authentication" ("area authentication" on page 200)

"area dead-interval" ("area dead-interval" on page 202)

"area filter" ("area filter" on page 203)

"area hello-interval" ("area hello-interval" on page 204)

"area nssa" ("area nssa" on page 205)

"area nssa-range" ("area nssa-range" on page 206)

"area nssa-translate-always" ("area nssa-translate-always" on page 207)

"area poll-interval" ("area poll-interval" on page 208)

"area priority" ("area priority" on page 209)

"area range" ("area range" on page 210)

"area retransmit-interval" ("area retransmit-interval" on page 211)

"area stub" ("area stub" on page 212)

"area stubhost" ("area stubhost" on page 213)

Fast Open Shortest Path First (OSPF) Overview

Fast Open Shortest Path First (OSPF) Page 169

"area stubnetwork" ("area stubnetwork" on page 214)

"area transmit-delay" ("area transmit-delay" on page 215)

"area virtual-link" ("area virtual-link" on page 216)

Default Commands

The following OSPF default commands are configured in OSPF Router Configuration Mode:

"default-metric" ("default-metric" on page 217)

"default-nssa-metric" ("default-nssa-metric" on page 218)

"default-nssa-type" ("default-nssa-type" on page 219)

"default-preference" ("default-preference" on page 219)

"default-tag" ("default-tag" on page 220)

"default-type" ("default-type" on page 221)

Area Interface Commands

The following commands are configured in Area Interface Configuration Mode:

"advertise-subnet" ("advertise-subnet" on page 222)

"allow-all" ("allow-all" on page 223)

"authentication" ("authentication" on page 223)

"cost" ("cost" on page 225)

"dead-interval" ("dead-interval" on page 226)

"enable" ("enable" on page 227)

"hello-interval" ("hello-interval" on page 228)

"neighbor" ("neighbor" on page 229)

"network" ("network" on page 230)

"no-multicast" ("no-multicast" on page 231)

"passive-interface" ("passive-interface" on page 232)

"poll-interval" ("poll-interval" on page 233)

"priority" ("priority" on page 234)

"retransmit-interval" ("retransmit-interval" on page 235)

"traffic-eng administrative-weight" ("traffic-eng administrative-weight" on page 236)

"traffic-eng attribute-flags" ("traffic-eng attribute-flags" on page 237)

"traffic-eng bandwidth" ("traffic-eng bandwidth" on page 238)

"transmit-delay" ("transmit-delay" on page 239)

Floating Interface Commands

The following commands are configured in Interface Configuration Mode:

"ip ospf advertise-subnet" ("ip ospf advertise-subnet" on page 240)

"ip ospf allow-all" ("ip ospf allow-all" on page 241)

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf authentication" ("ip ospf authentication" on page 242)

"ip ospf cost" ("ip ospf cost" on page 244)

"ip ospf dead-interval" ("ip ospf dead-interval" on page 245)

"ip ospf enable" ("ip ospf enable" on page 246)

"ip ospf hello-interval" ("ip ospf hello-interval" on page 247)

router ospf

Fast Open Shortest Path First (OSPF) Page 170

"ip ospf neighbor" ("ip ospf neighbor" on page 248)

"ip ospf network" ("ip ospf network" on page 248)

"ip ospf no-multicast" ("ip ospf no-multicast" on page 249)

"ip ospf passive-interface" ("ip ospf passive-interface" on page 250)

"ip ospf poll-interval" ("ip ospf poll-interval" on page 251)

"ip ospf priority" ("ip ospf priority" on page 252)

"ip ospf retransmit-interval" ("ip ospf retransmit-interval" on page 253)

"ip ospf traffic-eng administrative-weight" ("ip ospf traffic-eng administrative-weight" on page 254)

"ip ospf traffic-eng attribute-flags" ("ip ospf traffic-eng attribute-flags" on page 255)

"ip ospf traffic-eng bandwidth" ("ip ospf traffic-eng bandwidth" on page 256)

"ip ospf transmit-delay" ("ip ospf transmit-delay" on page 256)

Querying Commands

"show ip ospf" ("show ip ospf" on page 257)

"show ip ospf border-routers" ("show ip ospf border-routers" on page 258)

"show ip ospf database" ("show ip ospf database" on page 259)

"show ip ospf interface" ("show ip ospf interface" on page 260)

"show ip ospf neighbor" ("show ip ospf neighbor" on page 260)

"show ip ospf request-list" ("show ip ospf request-list" on page 261)

"show ip ospf retransmission-list" ("show ip ospf retransmission-list" on page 262)

"show ip ospf summary-address" ("show ip ospf summary-address" on page 263)

"show ip ospf virtual-links" ("show ip ospf virtual-links" on page 263)

router ospf

Name

router ospf - enters configuration mode for an instance in OSPF

Syntax

router ospf instance_id

no router ospf instance_id

Mode

Global Configuration

Parameters

instance_id - an integer from 1 to 4,294,967,294, inclusive, identifying the OSPF instance that you want to

configure

Description

Use the router ospf command to enter OSPF Router Configuration mode for an OSPF instance. Once

you are in OSPF Router Configuration mode, you can begin configuring a new OSPF instance or change an existing configuration.

Default

None. You must specify this command with an instance_id in order to configure OSPF.

advertise-subnet

Fast Open Shortest Path First (OSPF) Page 171

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows how to enter OSPF Router Configuration mode for OSPF instance 1.

(config)# router ospf 1

(config-router-ospf)#

advertise-subnet

Name

advertise-subnet - specifies whether OSPF will, when advertising point-to-point interfaces, advertise

the network number and netmask instead of a host route to the remote IP

Syntax

advertise-subnet

no advertise-subnet

Mode

OSPF Router Configuration

Parameters

none

Description

The advertise-subnet command specifies whether OSPF will, when advertising point-to-point

interfaces, advertise the network number and netmask of the point-to-point interface instead of a host route to the remote IP. Because the netmask is sometimes set improperly on point-to-point interfaces, this option disabled by default.

This command can be overridden at the area and interface levels.

Default

If advertise-subnet is not specified, it is the same as if the user had specified

the following: (config-router-ospf)# no advertise-subnet

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns the global advertise-subnet on, then turns it off for area 1.2.3.4.

(config)# router ospf 1

(config-router-ospf)# advertise-subnet

(config-router-ospf)# no area 1.2.3.4 advertise-subnet

(config-router-ospf)# exit

(config)#

See Also

"area advertise-subnet" ("area advertise-subnet" on page 199)

authentication

Fast Open Shortest Path First (OSPF) Page 172

"ip ospf advertise-subnet" ("ip ospf advertise-subnet" on page 240)

authentication

Name

authentication - specifies the type of OSPF authentication used and any key values

Syntax

authentication [ [simple key] | [ md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time) || (start-accept date_time) (stop-accept date_time)]? ] ]

no authentication [simple key | md5 id_number]

Mode

OSPF Router Configuration

Parameters

simple key - specifies simple (clear password) authentication. The value for key is specified as a one- to

eight-character string.

md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time)

|| (start-accept date_time) || (stop-accept date_time)] - specifies the authentication

used for specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is a one- to sixteen-character string. The start and stop values must be in the format: YYYY-MM-DD.HH.MM. Each start and stop value is optional, and order is not important when specifying multiple commands.

Description

Authentication can help to guarantee that routing information is imported only from trusted routers. A variety of authentication schemes can be used, but a single scheme must be configured for each network. The use of different schemes enables some interfaces to use much stricter authentication than others. The two authentication schemes available are simple, and MD5.

The authentication command specifies the type of global authentication and key values used in OSPF.

The negative form of this command removes authentication for the area. Authentication is used by OSPF to generate and verify the authentication field in the OSPF header. The global authentication is the default and can be overridden at the area command and interface levels.

When you want to keep certain routers from exchanging OSPF packets, use the simple form of authentication. The interfaces that the packets are to be sent on still need to be trusted, because the key will be placed in the packets and can be seen by anyone with access to the network.

When you do not trust other users of your network, use MD5 authentication. The system works by using shared secret keys. Because the keys are used to sign the packets with an MD5 checksum, they cannot be forged or tampered with. Because the keys are not included in the packet, snooping the key is not possible. Users of the network can still snoop the contents of packets, however, because the packets are not encrypted.

Advanced Routing Suite's MD5 authentication is compliant with the specification in OSPF RFC 2328. This specification uses the MD5 algorithm and an authentication key of up to 16 characters. RFC 2328 allows multiple MD5 keys per interface. Each key has associated time ranges.

Note: In order to turn off authentication, you must include the authentication type in the no form of the

command. For example, if MD5 authentication was configured, then simply specifying no

authentication will not work. In addition, you must specify the simple key when turning off simple

authentication, and you must specify the MD5 id_number when turning off MD5 authentication.

authentication

Fast Open Shortest Path First (OSPF) Page 173

Default

The default is for no authentication to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures simple authentication in OSPF instance 1.

(config)# router ospf 1

(config-router-ospf)# authentication simple abc

(config-router-ospf)# exit

(config)#

Example 2

The following example configures md5 authentication for OSPF instance 2. The ID for this md5 configuration is 1, and the key is configured as "bar".

(config)# router ospf 2

(config-router-ospf)# authentication md5 1 bar

(config-router-ospf)# exit

(config)#

Example 3

The following example turns off the MD5 authentication that was configured in Example 2. Note that specifying the MD5 key is not required, but specifying the MD5 ID is.

(config)# router ospf 2

(config-router-ospf)# no authentication md5 1

(config-router-ospf)# exit

(config)#

Example 4

The following example configures md5 authentication for OSPF instance 3. The md5 authentication is configured with a start-generate time set to January 02, 2004 at 21:30 hours, a stop-generate time set to January 02, 2004 at 21:45 hours, a start-accept time set to January 02, 2004 at 21:00 hours, and a stop-accept time set to January 02, 2004 at 22:00 hours.

(config)# router ospf 3

(config-router-ospf)# authentication md5 2 md5 start-generate 2004-01-02.21.30 stop-generate 2004-01-02.21.45 start-accept 2004-01-02.21.00 stop-accept 2004-01-02.22.00

(config-router-ospf)# exit

(config)#

See Also

"area authentication" ("area authentication" on page 200)

"ip ospf authentication" ("ip ospf authentication" on page 242)

compatible rfc1583

Fast Open Shortest Path First (OSPF) Page 174

compatible rfc1583

Name

compatible rfc1583 - specifies to run in RFC 1583 mode instead of RFC 2328 mode

Syntax

compatible rfc1583

no compatible rfc1583

Mode

OSPF Router Configuration

Parameters

none

Description

The compatible rfc1583 command specifies to run in RFC 1583 mode instead of RFC 2328 mode. Do

not specify this command if all the routers using an OSPF implementation in your domain are based on RFC 2328 or later. This option should be specified the same way on all routers in the domain. If any of the routers do not have this option, you should always enable this. When disabled, the preference rules for best route election are changed to eliminate certain kinds of possible routing loops.

The negative of this command, no compatible rfc1583, removes the requirement to run in RFC 1583

mode and reverts to RFC 2328 mode.

Default

If compatible rfc1583 is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# compatible rfc1583

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables RFC 1583 mode in for instance 1 of OSPF.

(config)# router ospf 1

(config-router-ospf)# no compatible rfc1583

(config-router-ospf)# exit

(config)#

dead-interval

Name

dead-interval - specifies the number of seconds that can elapse without receiving a router’s hello

packets before the router’s neighbors will declare it down

Syntax

dead-interval time-seconds

no dead-interval time-seconds?

distance

Fast Open Shortest Path First (OSPF) Page 175

Mode

OSPF Router Configuration

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying a time in seconds

Description

Use the global dead-interval command to specify the number of seconds that may elapse without

receiving a router’s hello packets before the router’s neighbors will declare it down. This value can be overridden at the area and interface levels. A general rule is for this value to equal three times the HELLO interval. Do not set this value to be less than the HELLO interval or convergence will not occur.

The negative form of this command, no dead-interval, removes the configured value and returns this to

its default value of 40 seconds. Note: Specifying a value for time-seconds in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If dead-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# dead-interval 40

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a global dead-interval value of 30. This value is then overridden in area 1.2.3.4 to be 25.

(config)# router ospf 1

(config-router-ospf)# dead-interval 30

(config-router-ospf)# area 1.2.3.4 dead-interval 25

(config-router-ospf)# exit

(config)#

See Also

"area dead-interval" ("area dead-interval" on page 202)

"ip ospf dead-interval" ("ip ospf dead-interval" on page 245)

distance

Name

distance - specifies how active routes that are learned from OSPF internal reachability will be selected,

compared to other protocols

Syntax

distance int_value

no distance int_value?

Mode

OSPF Router Configuration

enable

Fast Open Shortest Path First (OSPF) Page 176

Parameters

int_value - the Advanced Routing Suite preference for internal routes. This can be an integer from 1 to 255,

inclusive.

Description

The distance command specifies how active routes that are learned from the OSPF internal reachability

(compared to other protocols) will be selected. When a route has been learned from more than one protocol, the active route will be selected from the protocol with the lowest distance. Each protocol has a default distance in this selection.

The negative form of this command, no distance, removes the configured value and returns this to its

default value of 10.

Default

If distance is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# distance 10

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the default distance for internal routes to be 100.

(config)# router ospf 1

(config-router-ospf)# distance 100

(config-router-ospf)# exit

(config)#

enable

Name

enable - enables an OSPF instance

Syntax

enable

no enable

Mode

OSPF Router Configuration

Parameters

none

Description

The enable command enables the state for an OSPF instance. The negative form of this command, no

enable, disables the instance. If an enabled instance is disabled, then it is stopped, and all running state

is deleted. All configuration state, however, is preserved. If a disabled instance is enabled, it will start running again with its preserved configuration state.

Default

If enable is not specified, it is the same as if the user had specified the following:

enable-te

Fast Open Shortest Path First (OSPF) Page 177

(config-router-ospf)# enable

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables OSPF instance 3.

(config)# router ospf 3

(config-router-ospf)# no enable

(config-router-ospf)# exit

(config)#

enable-te

Name

enable-te - causes OSPF to originate Traffic Engineering (TE) information in Opaque LSAs

Syntax

enable-te

no enable-te

Mode

Global Configuration

Parameters

none

Description

Use the enable-te command to cause OSPF to originate TE information in Opaque LSA for all running

OSPF interfaces. This information does not affect normal OSFP routing and provides extra parameters for links and routers in the topology, such as available bandwidth.

Default

If enable-te is not specified, it is the same as if the user had specified the following:

(config)# no enable-te

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables Traffic Engineering LSAs for OSFP router instance 1.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)#

hello-interval

Fast Open Shortest Path First (OSPF) Page 178

hello-interval

Name

hello-interval - specifies the time in seconds between hello packets that the other router sends on an

interface

Syntax

hello-interval time-seconds

no hello-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The hello-interval command specifies the time in seconds between hello packets that the router send

on the interface. This option is specified here at the global level. It can be overridden in the area and interface levels. (See "area hello-interval" ("area hello-interval" on page 204) and "ip ospf hello-interval" ("ip ospf hello-interval" on page 247).)

The negative form of this command, no hello-interval, removes the configured value and returns this

to its default value of 10 seconds. Note: Specifying a value for time-seconds in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If hello-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# hello-interval 10

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a global hello interval of 15 seconds. This is then overridden in the area statement, where it is configured to be 5 seconds.

(config)# router ospf 1

(config-router-ospf)# hello-interval 15

(config-router-ospf)# area 1.2.3.4 hello-interval 5

(config-router-ospf)# exit

(config)#

See Also

"area hello-interval" ("area hello-interval" on page 204)

"ip ospf hello-interval" ("ip ospf hello-interval" on page 247)

igp-shortcut

Fast Open Shortest Path First (OSPF) Page 179

igp-shortcut

Name

igp-shortcut - enables the IGP shortcut feature for OSPF

Syntax

igp-shortcut

no igp-shortcut

Mode

OSPF Router Configuration

Parameters

none

Description

The igp-shortcut command enables the IGP Shortcut feature for OSPF. When configured, OSPF will

consider MPLS tunnels as uni-directional, directly connected, point-to-point links. To disable this feature, use the negative form of the command.

Default

If the igp-shortcut command is not explicitly configured, it is as if the user had configured the following:

(config-router-ospf)# no igp-shortcut

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following command enables the IGP Shortcut feature for OSPF instance 1.

(config)# router ospf 1

(config-router-ospf)# igp-shortcut

(config-router-ospf)# exit

(config)#

Example 2

The following command disables the IGP Shortcut feature for OSPF instance 1.

(config)# router ospf 1

(config-router-ospf)# no igp-shortcut

(config-router-ospf)# exit

(config)#

inherit-metric

Fast Open Shortest Path First (OSPF) Page 180

inherit-metric

Name

inherit-metric - configures an OSPF ASE route to inherit the metric of the external route when no

metric is specified on the export policy

Syntax

inherit-metric

no inherit-metric

Mode

OSPF Router Configuration

Parameters

none

Description

Use the inherit-metric command to allow an OSPF ASE route to inherit the metric of the external route

when no metric is specified on the export policy. This feature maintains compatibility with all the current export functions. A metric specified on the export policy takes precedence. The metric specified in the defaults section ("default-metric" ("default-metric" on page 217)) will be used if this command is not specified.

Default

If inherit-metric is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no inherit-metric

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures ASE routes exported into OSPF to inherit the metric of the external route.

(config)# router ospf 1

(config-router-ospf)# inherit-metric

(config-router-ospf)# exit

(config)#

monitor-auth-key

Name

monitor-auth-key - sets an authentication key when using the OSPF Monitor tool

Syntax

monitor-auth-key string

no monitor-auth-key string

Mode

OSPF Router Configuration

multicast-rib

Fast Open Shortest Path First (OSPF) Page 181

Parameters

string - a string of up to eight characters

Description

Use the monitor-auth-key command to set an authentication key when using the OSPF Monitor tool.

The negative form of this command, no monitor-auth-key, removes the password previously defined by

this command and reverts to the default of no password.

Default

If monitor-auth-key is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no monitor-auth-key

Command History

NGC 2.2 - This command was introduced.

Examples

The following example sets the monitor-auth-key authentication to "abc-auth".

(config)# router ospf 2

(config-router-ospf)# monitor-auth-key abc-auth

(config-router-ospf)# exit

(config)#

See Also

"Chapter 4 OSPF Monitor (ospfmon)" in Operating Advanced Routing Suite

multicast-rib

Name

multicast-rib - specifies the RIB in which OSPF internal routes are installed

Syntax

multicast-rib

no multicast-rib

Mode

OSPF Router Configuration

Parameters

none

Description

The multicast-rib command specifies the RIB into which OSPF internal routes are installed. The

unicast RIB is required and is the default. In code bases that support extended RIBs, OSPF routes can be installed in the multicast RIB.

This command has no effect on self-originated ASE or NSSA routes because they are exported from

another protocol. The negative form of this command, no multicast-rib reverts this back to its default of

no multicast-rib.

network area

Fast Open Shortest Path First (OSPF) Page 182

Default

If multicast-rib is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no multicast-rib

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures OSPF routes to be installed in the unicast and multicast RIBs.

(config)# router ospf 1

(config-router-ospf)# multicast-rib

(config-router-ospf)# exit

(config)#

network area

Name

network area - defines the interfaces on which OSPF will run, and defines the area ID for those

interfaces

Syntax

network ip_address wildcard-mask area area_id

no network ip_address wildcard-mask area area_id

Mode

OSPF Router Configuration

Parameters

ip_address - a valid IP address

wildcard-mask - IP-address-type mask that includes "don’t care" bits

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone. If you intend to associate areas with IP subnets, you

can specify a subnet address for this value.

Description

Use the network area command to specify interfaces on which OSPF runs and to define the area ID for

those interfaces. Use the negative form of this command, no network area, to disable OSPF routing for

any specified interfaces.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

nssa-inherit-metric

Fast Open Shortest Path First (OSPF) Page 183

Examples

Example 1

The following example defines network 192.168.10.5 0.0.0.255 in area 1.2.3.4

(config)# router ospf 1

(config-router-ospf)# network 192.168.10.5 0.0.0.255 area 1.2.3.4

(config-router-ospf)# exit

(config)#

Example 2

The following example disables OSPF routing on interface 102.168.10.10 in area 1.2.3.4.

(config)# router ospf 1

(config-router-ospf)# no network 192.168.10.10 0.0.0.0 area 1.2.3.4

(config-router-ospf)# exit

(config)#

nssa-inherit-metric

Name

nssa-inherit-metric - allows an OSPF NSSA route to inherit the metric of the external route when no

metric is specified on the export policy

Syntax

nssa-inherit-metric

no nssa-inherit-metric

Mode

OSPF Router Configuration

Parameters

none

Description

The nssa-inherit-metric command allows an OSPF NSSA route to inherit the metric of the external

route when no metric is specified on the export policy. This feature maintains compatibility with all the current export functions. A metric specified on the export policy will take precedence.

Default

If nssa-inherit-metric is not specified, it is the same as if the user had specified the following:

(config)# no nssa-inherit-metric

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures NSSA routes exported into OSPF to inherit the metric of the external route.

(config)# router ospf 1

nssa-stability-interval

Fast Open Shortest Path First (OSPF) Page 184

(config-router-ospf)# nssa-inherit-metric

(config-router-ospf)# exit

(config)#

nssa-stability-interval

Name

nssa-stability-interval - sets the length of time in seconds that an NSSA translator will continue to

translate after losing the translator election

Syntax

nssa-stability-interval time-seconds

no nssa-stability-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying an amount of time in seconds

Description

An NSSA ABR can translate Type 7 LSAs into Type 5 LSAs. A translator election is run to determine which one ABR for a given NSSA will translate. When an ABR was a translator and loses this election, it will cease translating after the amount of time specified by time-seconds. This allows the newly translated Type 5 LSAs from the new translator to be flooded throughout the domain before the currently translated Type 5 LSAs from this translator are flushed and the Type 5 LSAs resulting from direct translation are allowed to age out.

Default

If nssa-stability-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# nssa-stability-interval 40

Command History

NGC 2.2 - This command was introduced.

Examples

The following example sets the NSSA stability interval to 10 seconds.

(config)# router ospf 1

(config-router-ospf)# nssa-stability-interval 10

(config-router-ospf)# exit

(config)#

poll-interval

Name

poll-interval - specifies the length of time, in seconds, between OSPF packets that the router send

before adjacency is established with a neighbor

priority

Fast Open Shortest Path First (OSPF) Page 185

Syntax

poll-interval time-seconds

no poll-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The poll-interval command specifies the length of time, in seconds, between OSPF packets that the

router sends before an adjacency is established with a neighbor. Utilizing this command reduces network overhead in cases where a router may have a neighbor on a given interface at the expense of initial convergence time.

This value is configured here at the global level and can be overridden at the area and interface levels.

The negative form of this command, no poll-interval, removes the configured time-seconds value and

returns this to its default value of 120 seconds. Note: Specifying a value for time-seconds in the no form has

no effect on the configuration. Thus, it is displayed above as optional.

Default

If poll-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# poll-interval 120

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a global poll interval of 100 seconds. This value is overridden in interface fxp1, where it is configured to be 110 seconds.

(config)# router ospf 1

(config-router-ospf)# poll-interval 100

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf poll-interval 110

(config-if)# exit

(config)#

See Also

"area poll-interval" ("area poll-interval" on page 208)

"ip ospf poll-interval" ("ip ospf poll-interval" on page 251)

priority

Name

priority - specifies the priority for becoming the designated router (DR)

redistribute

Fast Open Shortest Path First (OSPF) Page 186

Syntax

priority level

no priority level?

Mode

OSPF Router Configuration

Parameters

level - a priority number between 0 and 255, inclusive, for becoming a DR

Description

The priority command specifies a number between 0 and 255 that configures the priority for becoming

the DR. When more than one router attached to a network attempts to become the DR, the one with the highest priority wins. If the competing routes have the same priority, the one with the highest router ID becomes the DR. The router coming in second in the election becomes the backup DR. A router with a router priority set to 0 is ineligible to become the DR.

This value is specified here at the global level and can be overridden at the area and interface levels ("area priority" ("area priority" on page 209) and "ip ospf priority" ("ip ospf priority" on page 252)). The negative

form of this command, no priority, removes the configured value and returns this to its default value of 0.

Note: Specifying a value for level in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Default

If priority is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# priority 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a global priority of 10. This value is then overridden in area 1.2.3.4, where it is configured to be 15.

(config)# router ospf 1

(config-router-ospf)# priority 10

(config-router-ospf)# area 1.2.3.4 priority 15

(config-router-ospf)# exit

(config)#

See Also

"area priority" ("area priority" on page 209)

"ip ospf priority" ("ip ospf priority" on page 252)

redistribute

Name

redistribute - specifies routes to export to OSPF

Syntax

redistribute protocol [route-map name]? {0,9}

redistribute

Fast Open Shortest Path First (OSPF) Page 187

no redistribute protocol [route-map name]?

Mode

OSPF Router Configuration

Parameters

protocol - the protocol name whose routes you want to redistribute to the current protocol being configured.

Valid protocols are aggregate, bgp, direct, isis, kernel, ospf, ospf-ase, rip, and static.

route-map name - the name of a route map to apply to these routes. Specifying this is optional.

{0,9} - although this command can be given multiple times, it can only be given once for each of the nine

configurable protocols. In other words, if a redistribute command is given for a protocol and route map,

and then given again for the same protocol with a different route map, the second configuration overrides the first.

Description

Use the redistribute command to specify routes to export into OSPF. This command causes routes

from the specified protocol to be considered for redistribution into the current protocol. Additionally, if a route map is specified, then routes from the specified protocol that match the named route map will be considered for redistribution into the current protocol. If the referenced route map has not yet been configured, then an empty route map is created with the specified name.

Note: Configuring this away from its default removes the implicitly configured default. You will have to go

back and specify to redistribute OSPF and direct routes after the first redistribute configuration in order

to export those routes.

Default

The default is to redistribute OSPF and the direct routes associated with the interfaces on which OSPF is running. Note that this is an implicit default that is wiped away with the first redistribute configuration.

Example

Example 1

In the following example OSPF instance 2 is configured to redistribute all BGP and RIP routes.

(config)# router ospf 2

(config-router-ospf)# redistribute bgp

(config-router-ospf)# redistribute rip

(config-router-ospf)# exit

(config)#

Example 2

The following example configures a community set, "set1", that permits AS:num 101:102. It then configures an extended community set "ext-set1", that permits Route Target AS:num 201:202.

(config)# ip community-set set1 permit 101:102

(config)# ip extcommunity-set ext-set1 permit rt 201:202

The two are then added to a community list, called "commlist1".

(config)# ip community-list commlist1 permit set1

(config)# ip community-list commlist1 permit ext-set1

The community list is then applied to a route map called "match-commlist1". If the route map matches BGP Community list "commlist1", then the metric for routes will be set to 20.

(config)# route-map match-commlist1

(config-route-map)# match community commlist1

redistribute-nssa

Fast Open Shortest Path First (OSPF) Page 188

(config-route-map)# set metric 20

(config-route-map)# exit

(config)#

Finally, the route map ("match-commlist1") is applied to BGP routes and exported into instance 1 of OSPF.

(config)# router ospf 1

(config-router-ospf)# redistribute bgp route-map match-commlist1

(config-router-ospf)# exit

(config)#

Example 3

In the following example, route map "abc" is configured with the following match criteria:

If a route matches interface "fxp1" and a pre-configured BGP Community labeled "bgpcomm1", then communities specified in community "com-set-1" will be added to the route, communities specified in community labeled "com-set-2" will be deleted from the route, and the metric of the route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match community-set bgpcomm1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

This route map is then applied to static routes and exported into OSPF instance 2.

(config)# router ospf 2

(config-router-ospf)# redistribute static route-map abc

(config-router-ospf)# exit

redistribute-nssa

Name

redistribute-nssa - specifies routes to export to OSPF NSSA in an OSPF instance

Syntax

redistribute-nssa protocol [route-map name]? {0,9}

no redistribute-nssa protocol [route-map name]?

Mode

OSPF Router Configuration

Parameters

protocol - the protocol name whose routes you want to redistribute to the current protocol being configured.

Valid protocols are aggregate, bgp, direct, kernel, isis, ospf, ospf-ase, rip, and static.

route-map name - the name of a route map to apply to these routes. Specifying this is optional.

{0,9} - although this command can be given multiple times, it can only be given once for each of the nine

configurable protocols. In other words, if a redistribute command is given for a protocol and route map,

require-vbit

Fast Open Shortest Path First (OSPF) Page 189

and then given again for the same protocol with a different route map, the second configuration overrides the first.

Description

Use the redistribute-nssa command to specify routes to export into all NSSA areas in the current

OSPF instance. This command causes routes from the specified protocol to be considered for redistribution into OSPF-NSSA. Additionally, if a route map is specified, then routes from the specified protocol that match the named route map will be considered for redistribution into OSPF-NSSA.

If the referenced route map has not yet been configured, then an empty route map is created with the specified name.

Default

The default is that OSPF does not redistribute any routes into NSSA.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a route map "abc" is configured to match all IPv4 prefixes (configured in prefix list "pl1"), to set the exported metric to 1, and to set the NSSA Propagate (P) bit.

(config)# ip prefix-list pl1 seq 1 permit 0.0.0.0/0 le 32

(config)# route-map abc

(config-route-map)# match ip address prefix-list pl1

(config-route-map)# set metric 1

(config-route-map)# set propagate

(config-route-map)# exit

(config)#

This route map is then applied to static routes and exported into OSPF NSSA.

(config)# router ospf 1

(config-router-ospf)# redistribute-nssa static route-map abc

(config-router-ospf)# exit

(config)#

require-vbit

Name

require-vbit - instructs the spf code to require that the vbit be set in the router LSAs of routers that are

the end points of virtual links

Syntax

require-vbit

no require-vbit

Mode

OSPF Router Configuration

Parameters

none

restart-allow-changes

Fast Open Shortest Path First (OSPF) Page 190

Description

Specifying this command instructs the SPF code to require that the vbit be set in the router LSAs of routers that are the end points of virtual links. When this command is not specified, the vbit can be clear, and the virtual link will still be considered.

This command exists to work around a bug in some OSPF implementations.

Default

If require-vbit is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no require-vbit

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns require-vbit on.

(config)# router ospf 1

(config-router-ospf)# require-vbit

(config-router-ospf)# exit

(config)#

restart-allow-changes

Name

restart-allow-changes - specifies whether changes in the network will cause any helper attempts to

fail

Syntax

restart-allow-changes

no restart-allow-changes

Mode

OSPF Router Configuration

Parameters

none

Description

The restart-allow-changes command specifies whether a change in the network (for example,

something that causes an SPF) will cause any helper attempts to fail. This command can be given for multiple instances.

Turning this command on configures the OSPF instance to cancel helper mode on all neighbors currently attempting a restart (either Graceful or Signaled) when a topology change occurs.

The negative form of this command, no restart-allow-changes configures the restart helper mode to

ignore topology change. Note that this can cause black holes to occur in the network.

Default

If restart-allow-changes is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no restart-allow-changes

restart-enable

Fast Open Shortest Path First (OSPF) Page 191

Command History

NGC 2.3 - This command was introduced.

Examples

The following example turns the allow changes helper flag on.

(config)# router ospf 1

(config-router-ospf)# restart-allow-changes

(config-router-ospf)# exit

restart-enable

Name

restart-enable - specifies to attempt a restart after the next startup

Syntax

restart-enable

no restart-enable

Mode

OSPF Router Configuration

Parameters

none

Description

This command configures the restart ability for an OSPF instance. If the restart-enable command is

configured for an instance when OSPF starts, and/or if Advanced Routing Suite is restarted with the -r flag

(see"The Command-line Options" in Operating Advanced Routing Suite), then OSPF will perform restart operations.

Because of the nature of the CLI, this command must be given during a "conf file replace" in order for it to apply to the current startup attempt. The reason is that all OSPF configuration must be in place before any of the configuration is committed. This can only be guaranteed with a conf file replace.

Notes:

A reconfiguration will not result in an attempted restart. Only occurrences that force the instance to be deleted and re-created will result in a restart.

This command overrides the -r flag given during a restart. For example, if no restart-enable is

configured for an instance, and then Advanced Routing Suite is restarted with the -r flag, restarts will

not take place.

Default

If the restart-enable command is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no restart-enable

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures OSPF to perform restart operations.

restart-max-sync-time

Fast Open Shortest Path First (OSPF) Page 192

(config)# router ospf 1

(config-router-ospf)# restart-enable

(config-router-ospf)# exit

(config)#

restart-max-sync-time

Name

restart-max-sync-time - configures the grace period in seconds for an unplanned restart attempt, for

an OSPF instance

Syntax

restart-max-sync-time time-seconds

no restart-max-sync-time time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - an integer from 1 to 65535, inclusive.

Description

The restart-max-sync-time command specifies the number of seconds that elapse before a restart

attempt will time out and fail. This command can configured for multiple instances. For graceful restart, this value represents the grace period. For signaled restart, if all adjacencies are not restored by this number of seconds after the restart attempt begins, then the attempt will fail.

Note: Either the "restart-enable" ("restart-enable" on page 191) command must be configured as "on" or

Advanced Routing Suite must be restarted with the -r flag (see "The Command-line Options" in Operating

Advanced Routing Suite) in order for this command to take effect.

The negative form of this command, no restart-max-sync-time, removes the configured time-seconds

value. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it

is displayed above as optional.

Default

If restart-max-sync-time is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# restart-max-sync-time 40

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures the period for a restart to be 30 seconds.

(config)# router ospf 1

(config-router-ospf)# restart-enable

(config-router-ospf)# restart-max-sync-time 30

(config-router-ospf)# exit

See Also

"restart-enable" ("restart-enable" on page 191)

restart-type

Fast Open Shortest Path First (OSPF) Page 193

restart-type

Name

restart-type - specifies whether the type of future restarts will be graceful or signaled

Syntax

restart-type [graceful | signaled]

no restart-type [graceful | signaled]?

Mode

OSPF Router Configuration

Parameters

graceful | signaled - specifies either graceful or signaled restart

Description

The restart-type command specifies the type of restart that will be attempted for future restarts. This

command can be given for multiple instances. For example, one instance can perform a graceful restart and one instance can perform a signaled restart, each at the same time.

Note: Either the "restart-enable" ("restart-enable" on page 191) command must be configured as "on" or

Advanced Routing Suite must be restarted with the -r flag (see "The Command-line Options" in Operating

Advanced Routing Suite) in order for this command to take effect.

Default

If the restart-type command is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# restart-type graceful

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a restart type of signaled for OSPF instance 3.

(config)# router ospf 3

(config-router-ospf)# restart-enable

(config-router-ospf)# restart-type signaled

(config-router-ospf)# exit

(config)#

See Also

"restart-enable" ("restart-enable" on page 191)

retransmit-interval

Name

retransmit-interval - specifies the number of seconds between link state advertisement (LSA)

retransmissions for adjacencies

router-id

Fast Open Shortest Path First (OSPF) Page 194

Syntax

retransmit-interval time-seconds

no retransmit-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The retransmit-interval command sets the default for the number of seconds between LSA

retransmissions for adjacencies. If a Link State Protocol (LSP) is not acknowledged within the number of seconds specified here, it is re-sent.

This command is specified here at the global level and can be overridden in the area and interface levels ("area retransmit-interval" ("area retransmit-interval" on page 211) and "ip ospf retransmit-interval" ("ip ospf retransmit-interval" on page 253)).

The negative form of this command, no retransmit-interval, removes the configured retransmit value

and returns this to its default value of 5 seconds. Note: Specifying a value for time-seconds in the no form

has no effect on the configuration. Thus, it is displayed above as optional.

Default

If retransmit-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# retransmit-interval 5

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the global retransmit interval to be 10 seconds. This value is then overridden in area 1.2.3.4, where it is configured to be 15 seconds.

(config)# router ospf 1

(config-router-ospf)# retransmit-interval 10

(config-router-ospf)# area 1.2.3.4 retransmit-interval 15

(config-router-ospf)# exit

(config)#

See Also

"area retransmit-interval" ("area retransmit-interval" on page 211)

"ip ospf retransmit-interval" ("ip ospf retransmit-interval" on page 253)

router-id

Name

router-id - sets the OSPF 32-bit router ID for the specified instance

Syntax

router-id rid_value

timers spf

Fast Open Shortest Path First (OSPF) Page 195

no router-id rid_value

Mode

OSPF Router Configuration

Parameters

rid_value - a 32-bit address in dotted-quad notation

Description

The router-id command sets the OSPF 32-bit router ID for the specified instance. If the Router ID is not

specified, then the instance uses the global default router ID. The negative form of this command, no

router-id, removes the configured router ID and returns this to its default value specified by the globally

defined Router ID.

Default

If router-id is not specified, the instance uses the globally specified Router ID. If that is not specified,

then the highest IP address will be used.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the OSPF router ID to be 4.3.2.1.

(config)# router ospf 1

(config-router-ospf)# router-id 4.3.2.1

(config-router-ospf)# exit

(config)#

timers spf

Name

timers spf - specifies the minimum time between when OSPF receives a topology change and when it

starts the SPF computation

Syntax

timers spf time-seconds

no timers spf time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - the minimum interval between SPF calculations, specified as an integer between 1 and

65535, inclusive

Description

Use the timers spf command to specify the minimum time between when OSPF receives a topology

change and when it starts the SPF computation. The negative form of this command, no timers spf,

removes the configured time value and returns this to its default value of 5.

trace file

Fast Open Shortest Path First (OSPF) Page 196

Default

If timers spf is not specified, it is the same as if the user had specified the following:

(config)# timers spf 5

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the SPF timer interval to be 15.

(config)# router ospf 1

(config-router-ospf)# timers spf 15

(config-router-ospf)# exit

(config)#

trace file

Name

trace file - specifies the file to receive tracing information, the size of the file, whether to overwrite

existing files, and the maximum number of files allowed

Syntax

trace file file_name [ no-timestamp || overwrite]?

no trace file file_name [no-timestamp || overwrite]?

Mode

OSPF Router Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For OSPF, the trace file command in OSPF Router Configuration

Mode specifies a file for tracing of all OSPF events. The negative form of this command disables this

tracing. The specific events that are traced are controlled by the trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config-router-ospf)# trace file /var/log/ospf.log no-timestamp

(config-router-ospf)# trace file /var/log/ospf.log

The option given in the second command completely replaces that given in the first.

trace flag

Fast Open Shortest Path First (OSPF) Page 197

Default

OSPF tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, OSPF tracing is written to the file "/var/tmp/ospf.log". No timestamp will display at the beginning of the trace lines.

(config)# router ospf 1

(config-router-ospf)# trace file /var/tmp/ospf.log no-timestamp

trace flag

Name

trace flag - specifies OSPF-specific tracing options as well as options that are common across all

protocols

Syntax

trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ db | ospf-state | drelect | spf | flood | debug ] ) | ( [ packets | hello | dd | lsr | lsu | lsa ] [ send | receive | send-receive ]? [detail?] )

no trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ db | ospf-state | drelect | spf | flood | debug ] ) | ( [ packets | hello | dd | lsr | lsu | lsa ] [ send | receive | send-receive ]? [detail?] )

Mode

OSPF Router Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

SPF-specific flags that do not allow associated actions:

[ ospf-state | drelect | db | spf | flood | debug ] - These OSPF-specific flags cannot be

associated with the send, receive, or send-receive action items. These flags are defined as follows:

ospf-state - trace OSPF state change information

transmit-delay

Fast Open Shortest Path First (OSPF) Page 198

drelect - trace the Designated Router operations

db - trace the link-state database operations

spf - trace the Shortest Path First (SPF) calculations

flood - trace the flooding procedure

debug - trace OSPF at the debugging level of detail

SPF-specific flags that allow associated actions:

[ packets | hello | dd | lsr | lsu | lsa ] - These OSPF-specific flags can be associated with

the send, receive, or send-receive action items. These flags are defined as follows:

packets - trace all OSPF link-state packets

hello - trace OSPF hello packets, which are used to determine neighbor reachability

dd - trace OSPF Database Description (DD) packets, which are used in synchronizing OSPF databases

lsr - trace OSPF link-state request packets, which are used in synchronizing OSPF databases

lsu - trace OSPF link-state update packets, which are used in synchronizing OSPF databases

lsa - trace OSPF link-state acknowledgement packets, which are used in synchronizing OSPF

databases

[ send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the trace flag command to specify tracing flags for OSPF tracing. Each flag must reside on its own

configuration line. For example, you cannot specify to trace both task and policy packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received link state request and hello messages are traced in detail. This tracing information will be written to the file /var/tmp/ospf.log.

(config)# router ospf 1

(config-router-ospf)# trace file /var/tmp/ospf.log

(config-router-ospf)# trace flag lsr send-receive detail

(config-router-ospf)# trace flag hello send-receive detail

transmit-delay

Name

transmit-delay - specifies the time in seconds required to transmit a link stat update

Syntax

transmit-delay time-seconds

area advertise-subnet

Fast Open Shortest Path First (OSPF) Page 199

no transmit-delay time-seconds?

Mode

OSPF Router Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The transmit-delay command sets the estimated number of seconds required to transmit a link state

update. This command takes into account transmission and propagation delays and must be greater than 0. The transmit delay is specified here at the global level. It can be overridden at the area and interface levels ("area transmit-delay" ("area transmit-delay" on page 215) and "ip ospf transmit-delay" ("ip ospf transmit-delay" on page 256)) as well as within a virtual link ("area virtual-link" ("area virtual-link" on page 216)).

The negative form of this command, no transmit-delay, removes the configured time-seconds value

and returns this to its default value of 1. Note: Specifying a value for time-seconds in the no form has no

effect on the configuration. Thus, it is displayed above as optional.

Default

If transmit-delay is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# transmit-delay 1

Example

The following example configures a global transmit delay of 5 seconds. This value is then overridden in area 1.2.3.4 to be 3 seconds.

(config)# router ospf 1

(config-router-ospf)# transmit-delay 5

(config-router-ospf)# area 1.2.3.4 transmit-delay 3

(config-router-ospf)# exit

(config)#

area advertise-subnet

Name

area advertise-subnet - specifies whether OSPF will, when advertising point-to-point interfaces,

advertise the network number and netmask instead of a host route to the remote IP

Syntax

area area_id advertise-subnet

no area area_id advertise-subnet

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

area authentication

Fast Open Shortest Path First (OSPF) Page 200

Description

The area advertise-subnet command specifies whether OSPF will, when advertising point-to-point

interfaces, advertise the network number and netmask of the point-to-point interface instead of a host route to the remote IP. Because the netmask is sometimes set improperly on point-to-point interfaces, this option disabled by default.

Configuring this command in an area overrides a global advertise-subnet command. Similarly, this command can be overridden in an interface command.

Default

If area advertise-subnet is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# no area area_id advertise-subnet

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns advertise-subnet on for area 1.2.3.4 and off for interface fxp1 in the same

area.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 advertise-subnet

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# no ip ospf advertise-subnet

(config-if)# exit

(config)#

See Also

"advertise-subnet" ("advertise-subnet" on page 171)

"ip ospf advertise-subnet" ("ip ospf advertise-subnet" on page 240)

area authentication

Name

area authentication - specifies the type of OSPF authentication used and any key values

Syntax

area area_id authentication [ [simple key] | [ md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time) || (start-accept date_time) (stop-accept date_time)]? ] ]

no area area_id authentication [ simple key | md5 id_number]

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format.

A value of 0.0.0.0 signals that the area is a backbone.

area authentication

Fast Open Shortest Path First (OSPF) Page 201

simple key - specifies simple (clear password) authentication. The value for key is specified as a one- to

eight-character string.

md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time)

|| (start-accept date_time) || (stop-accept date_time)] - specifies the authentication

used for specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is a one- to sixteen-character string. The start and stop values must be in the format: YYYY-MM-DD.HH.MM. Each start and stop value is optional, and order is not important when specifying multiple commands.

Description

Authentication can help to guarantee that routing information is imported only from trusted routers. A variety of authentication schemes can be used, but a single scheme must be configured for each network. The use of different schemes enables some interfaces to use much stricter authentication than others. The two authentication schemes available are simple, and MD5.

The area authentication command specifies the type of authentication and key values used in OSPF.

The negative form of this command removes authentication for the area. Authentication is used by OSPF to generate and verify the authentication field in the OSPF header. The global authentication is the default and can be overridden here in the area command. Similarly, this command can be overridden at the interface level.

When you want to keep certain routers from exchanging OSPF packets, use the simple form of authentication. The interfaces that the packets are to be sent on still need to be trusted, because the key will be placed in the packets and can be seen by anyone with access to the network.

When you do not trust other users of your network, use MD5 authentication. The system works by using shared secret keys. Because the keys are used to sign the packets with an MD5 checksum, they cannot be forged or tampered with. Because the keys are not included in the packet, snooping the key is not possible. Users of the network can still snoop the contents of packets, however, because the packets are not encrypted.

Advanced Routing Suite's MD5 authentication is compliant with the specification in OSPF RFC 2328. This specification uses the MD5 algorithm and an authentication key of up to 16 characters. RFC 2328 allows multiple MD5 keys per interface. Each key has two associated time ranges.

Note: In order to turn off authentication, you must include the authentication type in the no form of the

command. For example, if MD5 authentication was configured, then simply specifying no area

authentication will not work. In addition, you must specify the simple key when turning off simple

authentication, and you must specify the MD5 id_number when turning off MD5 authentication.

Default

The default is for no authentication to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures simple authentication in OSPF instance 1.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 authentication simple abc

(config-router-ospf)# exit

(config)#

Example 2

The following example configures md5 authentication for OSPF area 1.2.3.4. The ID for this md5 configuration is 1, and the key is configured as "bar".

(config)# router ospf 2

area dead-interval

Fast Open Shortest Path First (OSPF) Page 202

(config-router-ospf)# area 1.2.3.4 authentication md5 1 bar

(config-router-ospf)# exit

(config)#

Example 3

The following example turns off the MD5 authentication that was configured in Example 2. Note that specifying the MD5 key is not required, but specifying the MD5 ID is.

(config)# router ospf 2

(config-router-ospf)# no area 1.2.3.4 authentication md5 1

(config-router-ospf)# exit

(config)#

Example 4

The following example configures md5 authentication for OSPF instance 3. The md5 authentication is configured with a start-generate time set to January 02, 2004 at 21:30 hours, a stop-generate time set to January 02, 2004 at 21:45 hours, a start-accept time set to January 02, 2004 at 21:00 hours, and a stop-accept time set to January 02, 2004 at 22:00 hours.

(config)# router ospf 3

(config-router-ospf)# area 1.1.1.1 authentication md5 2 md5 start-generate 2004-01-02.21.30 stop-generate 2004-01-02.21.45 start-accept 2004-01-02.21.00 stop-accept 2004-01-02.22.00

(config-router-ospf)# exit

(config)#

See Also

"authentication" ("authentication" on page 172)

"ip ospf authentication" ("ip ospf authentication" on page 242)

area dead-interval

Name

area dead-interval - specifies the number of seconds that can elapse without receiving a router’s hello

packets before the router’s neighbors will declare it down

Syntax

area area_id dead-interval time-seconds

no area area_id dead-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

time-seconds - an integer between 1 and 65535, inclusive specifying an amount of time in seconds

area filter

Fast Open Shortest Path First (OSPF) Page 203

Description

Use the area dead-interval command to specify the amount of time, in seconds, that can elapse

without receiving a router’s hello packets before the router’s neighbors will declare it down. This command is specified here at the area level, and it can be overridden in the equivalent interface command. (See "ip ospf dead-interval" ("ip ospf dead-interval" on page 245).)

A general rule for configuring this value is that it should be equal to four times the HELLO interval. (See "area hello-interval" ("area hello-interval" on page 204).) Do not set this value to less than the HELLO interval because convergence will not occur.

The negative form of this command, no area dead-interval, removes the configured time-seconds

value and returns this to its default value of 40 seconds. Note: Specifying a value for time-seconds in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If area dead-interval is not configured, it is the same as if the user had specified the following:

(config-router-ospf)# area area_id dead-interval 40

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a dead-interval of 80 seconds for area 1.2.3.4, and a dead-interval of 60 seconds on interface fxp1.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 dead-interval 80

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf dead-interval 60

(config-if)# exit

(config)#

See Also

"dead-interval" ("dead-interval" on page 174)

"ip ospf dead-interval" ("ip ospf dead-interval" on page 245)

area filter

Name

area filter - filters incoming summary (type 3) LSAs for an area

Syntax

area area_id filter ipv4_address netmask

no area area_id filter ipv4_address netmask

Mode

OSPF Router Configuration

area hello-interval

Fast Open Shortest Path First (OSPF) Page 204

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

ipv4_address - a valid IPv4 filter address specified in dotted-quad format

netmask - a valid network mask specified in dotted-quad format

Description

The area filter command filters incoming summary (type 3) LSAs for the area. Any incoming summary

LSA that falls within the given range will not be advertised into the area. This command has no effect unless the router is an ABR. This command has no effect in Transit areas (i.e. areas containing a Virtual Link). It is recommended that this command only be used in stub or NSSA areas that have a default being originated into them. Otherwise, addresses falling within the range may not be reachable in the area.

The negative form of this command, no area filter, removes the configured address range from the

filter.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example filters summary LSAs in the range 192.168.2.0 255.255.255.0.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 filter 192.168.2.0 255.255.255.0

(config-router-ospf)# exit

(config)#

area hello-interval

Name

area hello-interval - specifies the length of time in seconds between Hello packets that the router

sends

Syntax

area area_id hello-interval time-seconds

no area area_id hello-interval time-seconds

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

time-seconds - an integer between 1 and 65535, inclusive, specifying an amount of time in seconds

area nssa

Fast Open Shortest Path First (OSPF) Page 205

Description

Use the area hello-interval command to specify the number of seconds between Hello packets sent

by this router. This command is specified here at the area level, and it can be overridden in the equivalent interface command. (See "ip ospf hello-interval" ("ip ospf hello-interval" on page 247).)

A general rule for configuring this value is that it should be equal to one-fourth the dead interval. (See "area dead-interval" ("area dead-interval" on page 202).) This value should never be less than the dead interval value.

The negative form of this command, no area hello-interval, removes the configured time-seconds

value and returns this to its default value of 10 seconds. Note: Specifying a value for time-seconds in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If area hello-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# area area_id hello-interval 10

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a hello interval of 20 seconds for area 1.2.3.4, and a hello interval of 15 seconds on interface fxp1.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 hello-interval 20

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf hello-interval 15

(config-if)# exit

(config)#

See Also

"area hello-interval" ("area hello-interval" on page 204)

"ip ospf hello-interval" ("ip ospf hello-interval" on page 247)

area nssa

Name

area nssa - configures the area as a Not So Stubby Area (NSSA) according to

draft-ietf-ospf-nssa-update-11

Syntax

area area_id nssa metric metric-type

no area area_id nssa

Mode

OSPF Router Configuration

area nssa-range

Fast Open Shortest Path First (OSPF) Page 206

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

metric - the default OSPF metric. This value can be an integer from 1 to 65535, inclusive. If area nssa is

configured, then the default is to not originate a default route into the area.

metric-type - specify 1 or 2 as the default metric type. Routes exported from the Advanced Routing Suite

routing table into OSPF default to becoming type 1 ASEs.

Description

The area nssa command configures the specified area as an NSSA according to

draft-ietf-ospf-nssa-update-11. If the router is an ABR and has the highest router ID of all the ABRs in the area, and no other ABR in the area is configured to translate always, it will translate Type 7 LSAs with the P-bit (set by the propagate flag in an export command) to Type 5 LSAs. When an ABR that was translating loses a translator election, it will cease translating, and after a number of seconds (determined by the "nssa-stability-interval" ("nssa-stability-interval" on page 184)), it will flush any Type 5 LSAs resulting from aggregation. Any Type 5 LSAs resulting from direct translation of Type 7 LSAs will be allowed to age out.

If metric is configured, then an ABR will originate a default route with that metric into the area. f there are any filters on the area, this will be a type-3 default. Otherwise it will be a type-7 default, with metric type of metric-type.

Note: NSSA and Stub are mutually exclusive.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example changes the default metric type to 2.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 nssa 10 2

(config-router-ospf)# exit

(config)#

area nssa-range

Name

area nssa-range - specifies the net ranges that should be translated into Type 5 LSas from NSSA Type

7 LSAs

Syntax

area area_id nssa-range ip_address mask [no-advertise]?

no area area_id nssa-range ip_address mask [no-advertise]?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

area nssa-translate-always

Fast Open Shortest Path First (OSPF) Page 207

ip_address - the IPv4 address associated with this range

mask - the network mask for the specified IP address

no-advertise - sets the address range status to DoNotAdvertise. The Type 3 summary LSA will not be

suppressed, and the component networks will remain hidden from other networks. Specifying this is optional.

Description

The area nssa-range command specifies the net ranges that should be translated into Type 5 LSas from

NSSA Type 7 LSAs. The default behavior is to translate Type 7 LSas that do no fall within a configured net range. This command is valid only in an NSSA. It will be ignored when configured in a non-NSSA.

Default

NSSA net ranges are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures an NSSA range on address 192.168.110.0 with a mask of 255.255.0.0.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 nssa-range 192.168.110.0 255.255.0.0

(config-router-ospf)# exit

(config)#

area nssa-translate-always

Name

area nssa-translate-always - allows an Area Border Router (ABR) to always translate Type 7 LSAs

into Type 5 LSAs for the specified area

Syntax

area area_id nssa-translate-always

no area area_id nssa-translate-always

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

Description

An NSSA ABR can translate Type 7 LSAs into Type 5 LSAs. Ordinarily, a translator election is run to determine which on ABR for a given NSSA will translate. This option, however, allows an ABR to always translate Type 7 LSAs into Type 5 LSAs for the containing area. If an ABR is configured to always translate, then no other ABR will translate unless it is also configured to always translate.

Default

If area nssa-translate-always is not specified, it is the same as if the user had specified the following:

area poll-interval

Fast Open Shortest Path First (OSPF) Page 208

(config-router-ospf)# no area area_id nssa-translate-always

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures area 1.2.3.4 to always translate Type 7 LSAs into Type 5 LSAs.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 nssa-translate-always

(config-router-ospf)# exit

(config)#

area poll-interval

Name

area poll-interval - specifies the length of time, in seconds, between OSPF packets that the router

send before adjacency is established with a neighbor

Syntax

area area_id poll-interval time-seconds

no area area_id poll-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

time-seconds - the length of time in seconds, specified as an integer between 1 and 65535, inclusive

Description

The area poll-interval command specifies the length of time, in seconds, between OSPF packets that

the router sends before adjacency is established with a neighbor. Utilizing this command reduces network overhead in cases where a router may have a neighbor on a given interface at the expense of initial convergence time.

Specifying a poll interval for an area overrides the default configured poll interval. Similarly, an interface-specific poll interval overrides a value configured here.

The negative form of this command, no area poll-interval, removes the configured time-seconds

value and returns this to its default value of 120 seconds. Note: Specifying a value for time-seconds in the

no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If area poll-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# area area_id poll-interval 120

Command History

NGC 2.2 - This command was introduced.

area priority

Fast Open Shortest Path First (OSPF) Page 209

Examples

The following example configures an area poll interval of 100 seconds. This value is overridden in interface fxp1, where it is configured to be 110 seconds.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 poll-interval 100

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf poll-interval 110

(config-if)# exit

(config)#

See Also

"poll-interval" ("poll-interval" on page 184)

"ip ospf poll-interval" ("ip ospf poll-interval" on page 251)

area priority

Name

area priority - specifies the priority for becoming the designated router (DR)

Syntax

area area_id priority level

no area area_id priority level?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

level - a priority number between 0 and 255, inclusive, for becoming a DR

Description

The area priority command specifies the priority for becoming the DR. The priority specified at the area

level can be overridden at the interface level. When more than one router attached to a network attempts to become the DR, the one with the highest priority wins. If the competing routers have the same priority, the one with the highest router ID becomes the DR. The router coming in second in the election becomes the backup DR. A router with a priority set to 0 is ineligible to become the DR.

Note: This command applies only to broadcast or NBMA media.

The negative form o f this command, no area priority, removes the configured priority and returns this

to its default value of 0. Note: Specifying a value for level in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If the area priority command is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# area area_id priority 1

area range

Fast Open Shortest Path First (OSPF) Page 210

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures an area priority of 10. It also configures the priority for interface fxp1 to be 5.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 priority 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf priority 5

(config-if)# exit

(config)#

See Also

"priority" ("priority" on page 185)

"ip ospf priority" ("ip ospf priority" on page 252)

area range

Name

area range - configures the scope of an area on an Area Border Router (ABR)

Syntax

area area_id range ip_address mask [no-advertise]?

no area area_id range ip_address mask [no-advertise]?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

ip_address - the IPv4 address associated with this range

mask - the network mask for the specified IP address

no-advertise - sets the address range status to DoNotAdvertise. The Type 3 summary LSA will not be

suppressed, and the component networks will remain hidden from other networks. Specifying this is optional.

Description

The area range command configures the scope of an area on an ABR. Intra-area LSAs that fall within the

specified ranges are not advertised into other areas as inter-area routes. Instead, the specified ranges are

advertised as summary network LSAs. If no-advertise is specified, the summary network LSAs and all

LSAs within the range are not advertised. Intra-area LSAs that do not fall into any range are also advertised as summary network LSAs.

On well-designed networks, the area range command reduces the amount of routing information

propagated between areas. The entries in this command can be either networks or subnetwork/mask-length pairs.

area retransmit-interval

Fast Open Shortest Path First (OSPF) Page 211

Specifying the area range command on a non-ABR will have no effect. The negative form of this

command removes the configured summarization.

Default

The area range command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures an area range on address 192.168.0.0 with a mask of 255.255.0.0.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 range 192.168.0.0 255.255.0.0

(config-router-ospf)# exit

(config)#

area retransmit-interval

Name

area retransmit-interval - specifies the number of seconds between link state advertisement (LSA)

retransmissions for adjacencies

Syntax

area area_id retransmit-interval time-seconds

no area area_id retransmit-interval time-seconds?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

time-seconds - an integer between 1 and 65535, inclusive, specifying a number of seconds

Description

The area retransmit-interval command sets the default for the number of seconds between LSA

retransmissions for adjacencies. If a Link State Protocol (LSP) is not acknowledged within the amount of time specified in this command, then it is re-sent. This setting is another convergence/network traffic trade-off.

This command overrides the global retransmit interval and can be overridden at the interface level. The

negative form of this command, no area retransmit-interval, removes the configured value and

returns this to its default value of 5 seconds. Note: Specifying a value for time-seconds in the no form has

no effect on the configuration. Thus, it is displayed above as optional.

Default

If area retransmit-interval is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# area area_id retransmit-interval 5

area stub

Fast Open Shortest Path First (OSPF) Page 212

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the retransmit interval for area 1.2.3.4 to be 10 seconds. This value is then overridden in interface fxp1, where it is configured to be 7 seconds.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 retransmit-interval 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf retransmit-interval 7

(config-if)# exit

(config)#

See Also

"retransmit-interval" ("retransmit-interval" on page 193)

"ip ospf retransmit-interval" ("ip ospf retransmit-interval" on page 253)

area stub

Name

area stub - configures an area as a stub area

Syntax

area area_id stub metric?

no area area_id stub metric?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

metric - an integer between 1 and 65535, inclusive. If a stub area is configured, then the default is to not

originate a default route into the area.

Description

The area stub command configures the specified area as a stub. A stub area is one in which there are no

ASE or NSSA routes. Each router in the area must specify that the area is a stub, or adjacencies will not form. If a metric is specified, then it is used to inject a default route into the area with the specified value originating form this router. A metric value should only be specified on an Area Border Router (ABR). It is possible to use stub on multiple ABRs and give them different metrics.

The negative of this command, no area stub, removes the configured stub area.

Note: NSSA and stub are mutually exclusive.

Default

The default type of area is non-stub and non-NSSA. The default for a stub area is to not advertise a type-3 summary. A default is only originated if a cost is given.

area stubhost

Fast Open Shortest Path First (OSPF) Page 213

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures area 4.3.2.1 as a stub area with a metric of 15.

(config)# router ospf

(config-router-ospf)# area 4.3.2.1 stub 15

(config-router-ospf)# exit

(config)#

area stubhost

Name

area stubhost - specifies directly attached hosts that should be advertised as reachable from the router

and the metrics with which they should be advertised

Syntax

area area_id stubhost ip_address metric_value

no area area_id stubhost ip_address metric_value

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

ip_address - the address of the host to be advertised

metric_value - the metric to be advertised for the host specified as an integer between 1 and 65535,

inclusive. If a stubhost is configured, then this value defaults to 10.

Description

Use the area stubhost command to specify directly attached hosts that should be advertised as

reachable from the router and the metrics with which they should be advertised. Point-to-point interfaces on which it is not desirable to run OSPF should be specified here. It is also useful to assign an additional address to the loopback interface (one not on the 127 network) and advertise it as a stubhost.

If this address is the same as the router ID, it enables routing to OSPF routers by router ID instead of by interface address. Routing by router ID is more reliable than routing to one of the router’s interface addresses, which may not always be reachable.

The negative of this command, no area stubhost, removes the configured stubhost.

Note: This command is identical to "area stubnetwork" ("area stubnetwork" on page 214) in function except that a 32-bit mask is assumed.

Default

The area stubhost command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

area stubnetwork

Fast Open Shortest Path First (OSPF) Page 214

Examples

The following example configures a single stubhost, 192.1.1.1 with a metric of 2 in area 1.2.3.4.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 stubhost 192.1.1.1 2

(config-router-ospf)# exit

(config)#

area stubnetwork

Name

area stubnetwork - specifies directly attached networks that should be advertised as reachable from this

router and the metrics with which they should be advertised

Syntax

area area_id stubnetwork ip_address mask metric

no area area_id stubnetwork ip_address mask metric

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

ip_address - the address of the host to be advertised

mask - a mask for a network prefix specified in dotted-quad format

metric - the metric for the stubnetwork specified as an integer between 1 and 65535, inclusive. If a

stubnetwork is configured, then this value defaults to 10.

Description

Use the area stubnetwork command to specify directly attached networks that should be advertised as

reachable from this router. Interfaces on which it is not desirable to run OSPF should be specified here. No checking is currently done on whether the specified network is actually reachable from this router, so care should be taken.

The negative form of this command, no area stubnetwork, removes the configured stubnetwork.

Note: This command is identical to "area stubhost" ("area stubhost" on page 213) in function except that a 32-bit mask is not assumed and, therefore, must be configured.

Default

The area stubnetwork command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a single stubnetwork, 192.168.10 with a netmask of 24 in area 1.2.3.4.

(config)# router ospf 2

(config-router-ospf)# area 1.2.3.4 stubnetwork 192.168.10 255.255.255.0

(config-router-ospf)# exit

area transmit-delay

Fast Open Shortest Path First (OSPF) Page 215

(config)#

area transmit-delay

Name

area transmit-delay - specifies the number of seconds required to transmit a link state update

Syntax

area area_id transmit-delay time-seconds

no area area_id transmit-delay time-seconds?

Mode

OSPF Router Configuration

Parameters

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The area transmit-delay command sets the estimated number of seconds required to transmit a link

state update. This value takes into account transmission and propagation delays and must be greater than 0.

This value overrides the global transmit-delay value and can be overridden at the interface level. The

negative form of this command, no area transmit-delay, removes the configured value and returns this

to its default value of 1 second. Note: Specifying a value for time-seconds in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If area transmit-delay is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# area area_id transmit-delay 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the transmit-delay for area 1.2.3.4 to be 10 seconds. This value is then overridden on interface fxp1, where it is configured to be 5 seconds.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 transmit-delay 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf transmit-delay 5

(config-if)# exit

(config)#

See Also

"transmit-delay" ("transmit-delay" on page 198)

area virtual-link

Fast Open Shortest Path First (OSPF) Page 216

"ip ospf transmit-delay" ("ip ospf transmit-delay" on page 256)

area virtual-link

Name

area virtual-link - configures a virtual link on the backbone

Syntax

area transit_area virtual-link neighbor-id [ authentication [ (md5 id md5key) | (simple key) ] ]? || [(hello-interval time-seconds) ]? || [(retransmit-interval time-seconds) ]? || [(transmit-delay time-seconds) ]? || [(dead-interval time-seconds) ]?

no area transit_area virtual-link neighbor-id [ authentication [ (md5 id md5key) | (simple key) ] ]? || [(hello-interval time-seconds) ]? || [(retransmit-interval time-seconds) ]? || [(transmit-delay time-seconds) ]? || [(dead-interval time-seconds) ]?

Mode

OSPF Router Configuration

Parameters

transit_area - an ID, in dotted-quad format, that sets the area through which the virtual link should exist.

This value cannot be 0.0.0.0.

neighbor-id - the ID of one end of the virtual link

[authentication [ (md5 id "md5key") | (simple "key") ]] - optionally specify an authentication

type to include on this virtual link. md5 id md5_key specifies the authentication used for specifying md5

cryptographic authentication. The value for id is an integer between 1 and 255, inclusive. The value for

md5_key is a one- to sixteen-character string. simple key specifies simple (clear password) authentication.

The value for key is as a one- to eight-character string.

hello-interval time-seconds - optionally specify the time in seconds between hello packets that the

IOS software sends on an interface. This value must be an unsigned integer and must be the same for all routers and access servers attached to a common network. The default value is 10 seconds.

retransmit-interval time-seconds - optionally specify the time in seconds between link state

advertisement (LSA) retransmissions for adjacencies belonging on the interface. This value must be an integer and must be greater than the expected round-trip delay. The default value is 5 seconds.

transmit-delay time-seconds - optionally specify the time in seconds required to send a link state

update packet on the interface. This value must be an integer greater than 0. LSAs in the update packet have their age incremented by this amount before transmission. The default value is 1 second.

dead-interval time-seconds - optionally specify the time in seconds that Hello packets are sent

before a neighbor declares the router down. The default value is four times the hello-interval, or 40 seconds. If this value is configured less than the hello-interval, convergence will not occur. This value must be the same for all routers and access servers attached to a common network.

Description

Virtual links are used to establish or increase connectivity of the backbone area. The transit_area sets the area through which the virtual link should exist. The neighbor-id represents one end of the virtual link. In addition, all standard interface parameters can optionally be specified on a virtual link.

default-metric

Fast Open Shortest Path First (OSPF) Page 217

The negative form of this command, no area virtual-link, removes the configured virtual link. The

transit_area and neighbor-id parameters are the minimum required in the negative form of this command to remove the entire virtual link.

Default

The default is for no virtual links to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a virtual link in transit area 1.1.1.1 with a neighbor ID of 1.2.2.1, a hello interval of 20 seconds, and a retransmit interval of 20 seconds.

(config)# router ospf 1

(config-router-ospf)# area 1.1.1.1 virtual-link 1.2.2.1 hello-interval 20 retransmit-interval 20

(config-router-ospf)# exit

(config)#

default-metric

Name

default-metric - specifies the default ASE export metric

Syntax

default-metric metric_value

no default-metric metric_value?

Mode

OSPF Router Configuration

Parameters

metric_value - an integer assigned to exported reachability, specified as a value between 1 and 65535,

inclusive

Description

This command is used when exporting a non-OSPF route from the Advanced Routing Suite routing table

into OSPF as an ASE route. The default-metric command can be explicitly overridden in export policy.

The negative of this command, no default-metric, removes the configured value and returns this to its

default value of 10. Note: Specifying a value for metric_value in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If default-metric is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# default-metric 10

Command History

NGC 2.2 - This command was introduced.

default-nssa-metric

Fast Open Shortest Path First (OSPF) Page 218

Examples

The following example configures a default metric of 5 for instance 1.

(config)# router ospf 1

(config-router-ospf)# default-metric 5

(config-router-ospf)# exit

(config)#

default-nssa-metric

Name

default-nssa-metric - specifies the default cost when exporting non-OSPF routes into OSPF NSSA

Syntax

default-nssa-metric metric_value

no default-nssa-metric metric_value?

Mode

OSPF Router Configuration

Parameters

metric_value - an integer assigned to exported reachability, specified as a value between 1 and 65535,

inclusive

Description

default-nssa-metric is used when exporting a non-OSPF route from the Advanced Routing Suite

routing table into OSPF as an NSSA route. This command configures the default metric on originated NSSA

routes for an OSPF instance. default-nssa-metric can be explicitly overridden in export policy.

The negative form of this command, no default-nssa-metric, removes the configured value and

returns the metric_value to its default of 1. Note: Specifying a value for metric_value in the no form has

no effect on the configuration. Thus, it is displayed above as optional.

Default

If default-nssa-metric is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# default-nssa-metric 10

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the default NSSA metric for OSPF instance 1 to be 4.

(config)# router ospf 1

(config-router-ospf)# default-nssa-metric 4

(config-router-ospf)# exit

(config)#

default-nssa-type

Fast Open Shortest Path First (OSPF) Page 219

default-nssa-type

Name

default-nssa-type - changes the default type of routes exported from the Advanced Routing Suite

routing table into OSPF NSSA

Syntax

default-nssa-type [1 | 2]

no default-nssa-type [1 | 2]?

Mode

OSPF Router Configuration

Parameters

1 | 2 - sets the default metric type to 1 or 2

Description

The default-nssa-type command sets the default NSSA metric type to either 1 or 2. Routes exported

from the Advanced Routing Suite routing table into OSPF default to becoming type 1 NSSAs. This default can be explicitly change here and overridden in export policy.

The negative form of this command, no default-nssa-type, removes the configured value and returns

this to its default value of 1. Note: Specifying type 1 or 2 in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If default-nssa-type is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# default-nssa-type 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example changes the default NSSA Type to 2.

(config)# router ospf 2

(config-router-ospf)# default-nssa-type 2

(config-router-ospf)# exit

(config)#

default-preference

Name

default-preference - specifies the way that active routes learned from the OSPF ASE will be selected,

compared to other routes

Syntax

default-preference pref

no default-preference pref?

default-tag

Fast Open Shortest Path First (OSPF) Page 220

Mode

OSPF Router Configuration

Parameters

pref - an integer between 1 and 255, inclusive

Description

The default-preference command specifies how active routes that are learned from the OSPF ASE

(compared to other routes) will be selected. When a route has been learned from more than one protocol, the active route will be selected from the protocol with the lowest preference. Each protocol has a default preference in this selection.

The negative form of this command, no default-preference, removes the configured preference value

and returns this to its default value of 10. Note: Specifying a value for pref in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If default-preference is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# default-preference 10

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the OSPF default preference value to be 100.

(config)# router ospf 2

(config-router-ospf)# default-preference 100

(config-router-ospf)# exit

default-tag

Name

default-tag - used to propagate data from an exterior gateway protocol (such as BGP) through OSPF

Syntax

default-tag tag_value

no default-tag tag_value?

Mode

OSPF Router Configuration

Parameters

tag_value - a integer from 0 to 2147483647, inclusive

Description

OSPF ASE routes have a 32-bit tag field that is not used by the OSPF protocol but can be used when exporting to protocols other than OSPF. This command sets the tag, which can be overridden in export policy.

default-type

Fast Open Shortest Path First (OSPF) Page 221

The negative form of this command, no default-tag, removes the configured tag value and returns this

to its default value of 0. Note: Specifying a value for tag_value in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If default-tag is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# default-tag 0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the default tag value to be 10.

(config)# router ospf 1

(config-router-ospf)# default-tag 10

(config-router-ospf)# exit

(config)#

default-type

Name

default-type - changes the default type of routes exported from the Advanced Routing Suite routing

table into OSPF ASE

Syntax

default-type [1 | 2]

no default-type [1 | 2]?

Mode

OSPF Router Configuration

Parameters

1 | 2 - sets the default metric type to 1 or 2

Description

Routes exported from the Advanced Routing Suite routing table into OSPF default to becoming type 2 ASEs. This default can be explicitly changed here and overridden in export policy.

The negative form of this command, no default-type, removes the configured value and returns this to

its default value of 1. Note: Specifying 1 or 2 as the type in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If default-type is not specified, it is the same as if the user had specified the following:

(config-router-ospf)# default-type 2

Command History

NGC 2.2 - This command was introduced.

advertise-subnet

Fast Open Shortest Path First (OSPF) Page 222

Examples

The following example changes the default metric type to 1.

(config)# router ospf 2

(config-router-ospf)# default-type 1

(config-router-ospf)# exit

(config)#

advertise-subnet

Name

advertise-subnet - specifies whether OSPF will, when advertising point-to-point interfaces, advertise

the network number and netmask of the point-to-point interface instead of a host route to the remote IP

Syntax

advertise-subnet

no advertise-subnet

Mode

Area Interface Configuration

Parameters

none

Description

The advertise-subnet command specifies whether OSPF will, when advertising point-to-point

interfaces, advertise the network number and netmask of the point-to-point interface instead of a host route to the remote IP. Because the netmask is sometimes set improperly on point-to-point interfaces, this option disabled by default.

Default

If advertise-subnet is not specified, it is the same as if the user had specified the following:

(config-if-ip-ospf)# no advertise-subnet

Command History

NGC 2.3 - This command was introduced.

Examples

The following example turns advertise-subnet on for area 2.2.2.2 on interface ppp0.

(config)# interface ppp0

(config-if)# ip ospf 1 area 2.2.2.2

(config-if-ip-ospf)# advertise-subnet

(config-if-ip-ospf)# exit

(config-if)#

See Also

"ip ospf area" ("ip ospf area" on page 241)

allow-all

Fast Open Shortest Path First (OSPF) Page 223

allow-all

Name

allow-all - permits packets from all routers

Syntax

allow-all

no allow-all

Mode

Area Interface Configuration

Parameters

none

Description

The allow-all command specifies to allow packets from all routers, including those not specified in the

"neighbor" ("neighbor" on page 229) command.

Default

If allow-all is not specified, it is the same as if the user had specified the following:

(config-if-ip-ospf)# no allow-all

Command History

NGC 2.3 - This command was introduced.

Examples

The following example specifies that area 1.2.3.4 on interface fxp1 will allow packets from all routers.

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# allow-all

(config-if-ip-ospf)# exit

(config-if)#

See Also

"ip ospf area" ("ip ospf area" on page 241)

authentication

Name

authentication - specify the type of authentication and key values for an interface

Syntax

authentication [ [simple key] | [ md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time) || (start-accept date_time) (stop-accept date_time)]? ] ]

no authentication [ simple key | md5 id_number ]

authentication

Fast Open Shortest Path First (OSPF) Page 224

Mode

Area Interface Configuration

Parameters

simple key - specifies simple (clear password) authentication. The value for key is specified as a one- to

eight-character string.

md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time)

|| (start-accept date_time) || (stop-accept date_time)] - specifies the authentication

used for specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is a one- to sixteen-character string. The start and stop values must be in the format: YYYY-MM-DD.HH.MM. Each start and stop value is optional, and order is not important when specifying multiple commands.

Description

Authentication can help to guarantee that routing information is imported only from trusted routers. A variety of authentication schemes can be used, but a single scheme must be configured for each network. The use of different schemes enables some interfaces to use much stricter authentication than others. The two authentication schemes available are simple, and MD5.

The authentication command specifies the type of authentication and key values used for an area on

an interface. This is used by OSPF authentication to generate and verify the authentication field in the OSPF header. If configured, the area authentication ("area authentication" ("area authentication" on page 200)) is the default unless it is configured here at the area interface level.

When you want to keep certain routers from exchanging OSPF packets, use the simple form of authentication. The interfaces that the packets are to be sent on still need to be trusted, because the key will be placed in the packets and can be seen by anyone with access to the network.

When you do not trust other users of your network, use MD5 authentication. The system works by using shared secret keys. Because the keys are used to sign the packets with an MD5 checksum, they cannot be forged or tampered with. Because the keys are not included in the packet, snooping the key is not possible. Users of the network can still snoop the contents of packets, however, because the packets are not encrypted.

Advanced Routing Suite's MD5 authentication is compliant with the specification in OSPF RFC 2328. This specification uses the MD5 algorithm and an authentication key of up to 16 characters. RFC 2328 allows multiple MD5 keys per interface. Each key has two associated time ranges.

Note: In order to turn off authentication, you must include the authentication type in the no form of the

command. For example, if MD5 authentication was configured, then simply specifying no

authentication will not work. In addition, you must specify the simple key when turning off simple

authentication, and you must specify the MD5 id_number when turning off MD5 authentication.

Default

Authentication is not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

Example 1

The following example configures the global authentication to be the simple keyword "abc". This authentication is then overridden for area 1.2.3.4 on interface fxp0 to be "bar".

(config)# router ospf 1

(config-router-ospf)# authentication simple abc

(config-router-ospf)# exit

(config)# interface fxp1

cost

Fast Open Shortest Path First (OSPF) Page 225

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# authentication simple bar

(config-if-ip-ospf)# exit

(config-if)#

Example 2

The following example configures md5 authentication for area 2.2.2.2 on interface fxp1. The ID for this md5 configuration is 1, and the key is configured as "bar".

(config)# interface fxp1

(config-if)# ip ospf 1 area 2.2.2.2

(config-if-ip-ospf)# authentication md5 1 bar

(config-if-ip-ospf)# exit

(config-if)#

Example 3

The following example turns off the MD5 authentication that was configured in Example 2.

(config)# interface fxp1

(config-if)# ip ospf 1 area 2.2.2.2

(config-if-ip-ospf)# no authentication md5 1

(config-if-ip-ospf)# exit

(config-if)#

Example 4

The following example configures md5 authentication for area 4.3.2.1 on interface fxp3. The md5 authentication is configured with a start-generate time set to January 02, 2004 at 21:30 hours, a stop-generate time set to January 02, 2004 at 21:45 hours, a start-accept time set to January 02, 2004 at 21:00 hours, and a stop-accept time set to January 02, 2004 at 22:00 hours.

(config)# interface fxp3

(config-if)# ip ospf 1 area 4.3.2.1

(config-if-ip-ospf)# authentication md5 2 md5 start-generate 2004-01-02.21.30 stop-generate 2004-01-02.21.45 start-accept 2004-01-02.21.00 stop-accept 2004-01-02.22.00

(config-if-ip-ospf)# exit

(config-if)#

See Also

"authentication" ("authentication" on page 172)

"area authentication" ("area authentication" on page 200)

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf authentication" ("ip ospf authentication" on page 242)

cost

Name

cost - specifies the cost for a route to transmit an interface

dead-interval

Fast Open Shortest Path First (OSPF) Page 226

Syntax

cost cost_value

no cost cost_value?

Mode

Area Interface Configuration

Parameters

cost_value - the cost to be associated with this interface, specified as an integer between 1 and 65535

Description

The cost command is used for specifying the cost for a route to transmit an interface. This command can

be explicitly overridden in export policy. The negative form of this command, no cost, removes the

configured cost and returns this to its default value of 1. Note: Specifying a value for cost_value in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If cost is not specified, it is the same as if the user had specified the following:

(config-if-ip-ospf)# cost 10

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures the cost for area 1.2.3.4 on interface fxp1 to be 15.

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# cost 15

(config-if-ip-ospf)# exit

(config-if)#

See Also

"ip ospf area" ("ip ospf area" on page 241)

dead-interval

Name

dead-interval - specifies the number of seconds that may elapse on this interface without receiving a

router’s hello packets before the router’s neighbors will declare it down

Syntax

dead-interval time-seconds

no dead-interval time-seconds?

Mode

Area Interface Configuration

enable

Fast Open Shortest Path First (OSPF) Page 227

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying an amount of time in seconds

Description

Use the dead-interval command to specify the amount of time, in seconds, that can elapse without

receiving a router’s hello packets before the router’s neighbors will declare it down. This command is specified here at the interface level. It overrides a dead-interval configured at the area and global levels.

A general rule for configuring this value is that it should be equal to four times the HELLO interval. (See "hello-interval" ("hello-interval" on page 178).) Do not set this value to less than the HELLO interval because convergence will not occur.

The negative form of this command, no dead-interval, removes the configured time-seconds value and

returns this to its default value of 40 seconds. Note: Specifying a value for time-seconds in the no form has

no effect on the configuration. Thus, it is displayed above as optional.

Default

If dead-interval is not specified, it defaults to the value specified in "area dead-interval" ("area

dead-interval" on page 202) then the global "dead-interval" ("dead-interval" on page 174). If neither of these is specified, however, then it is the same as if the user had specified the following:

(config-if-ip-ospf)# dead-interval 40

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a global dead-interval of 80 seconds and a dead-interval of 60 seconds for area 1.2.3.4 on interface fxp1.

(config)# router ospf 1

(config-router-ospf)# dead-interval 80

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# dead-interval 60

(config-if-ip-ospf)# exit

(config-if)#

See Also

"dead-interval" ("dead-interval" on page 174)

"area dead-interval" ("area dead-interval" on page 202)

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf dead-interval" ("ip ospf dead-interval" on page 245)

enable

Name

enable - enables OSPF on an interface

Syntax

enable

hello-interval

Fast Open Shortest Path First (OSPF) Page 228

no enable

Mode

Area Interface Configuration

Parameters

none

Description

The enable command specifies to run OSPF on an interface.

Default

By default, OSPF runs on configured interfaces. Therefore, if enable is not specified, it is the same as if the

user had specified the following:

(config-if-ip-ospf)# enable

Command History

NGC 2.3 - This command was introduced.

Examples

The following example disables interface fxp1 for area 1.2.3.4.

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# no enable

(config-if-ip-ospf)# exit

(config-if)#

See Also

"ip ospf area" ("ip ospf area" on page 241)

hello-interval

Name

hello-interval - specifies the length of time in seconds between hello packets that the router sends on

the interface for the specified area

Syntax

hello-interval time-seconds

no hello-interval time-seconds?

Mode

Area Interface Configuration

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying an amount of time in seconds

Description

Use the hello-interval command to specify the number of seconds between Hello packets sent by the

router on this interface for the specified area. This command overrides the interval configured in the

neighbor

Fast Open Shortest Path First (OSPF) Page 229

equivalent global and area commands. (See "hello-interval" ("hello-interval" on page 178) and "area hello-interval" ("area hello-interval" on page 204).)

A general rule for configuring this value is that it should be equal to one-fourth the dead interval. (See "dead-interval" ("dead-interval" on page 226).) This value should never be less than the dead interval value.

The negative form of this command, no hello-interval, removes the configured time-seconds value.

Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

Default

If hello-interval is not specified, it defaults to the value specified in "area hello-interval" ("area

hello-interval" on page 204) then in the global "hello-interval" ("hello-interval" on page 178). If neither the area nor global hello interval is specified, however, then it is the same as if the user had specified the following:

(config-if-ip-ospf)# hello-interval 10

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a global hello interval of 20 seconds and a hello interval of 15 seconds for area 1.2.3.4 on interface fxp1.

(config)# router ospf 1

(config-router-ospf)# hello-interval 20

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# hello-interval 15

(config-if-ip-ospf)# exit

(config-if)#

See Also

"hello-interval" ("hello-interval" on page 178)

"area hello-interval" ("area hello-interval" on page 204)

"ip ospf area" ("ip ospf area" on page 241)

neighbor

Name

neighbor - specifies neighboring routes, and specifies whether those routes are eligible to become the

designated router (DR)

Syntax

neighbor ip_address [eligible]?

no neighbor ip_address [eligible]?

Mode

Area Interface Configuration

network

Fast Open Shortest Path First (OSPF) Page 230

Parameters

ip_address - a valid IPv4 address specified in dotted-quad notation

eligible - optionally specify whether the indicated address is eligible to become the DR

Description

By definition it is not possible to send broadcast or multicast packets to discover OSPF neighbors on a non-broadcast medium, so all neighbors must be configured. The host address list includes one or more

neighbors. The eligible option is used to indicate an address’s eligibility to become a DR. Refer to

section 9.5.1 of RFC 2328 for more information.

The negative form of this command, no neighbor, removes the configured neighbors.

Default

OSPF neighbors are not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

The following example specifies that host 10.1.1.1 is eligible to become a DR in area 2.2.2.2.

(config)# interface fxp1

(config-if)# ip ospf 1 area 2.2.2.2

(config-if-ip-ospf)# neighbor 10.1.1.1 eligible

(config-if-ip-ospf)# exit

See Also

"ip ospf area" ("ip ospf area" on page 241)

network

Name

network - specifies a either a nonbroadcast interface on an NBMA medium or a point-to-multipoint

interface

Syntax

network [ nonbroadcast | point-to-multipoint ]

no network [ nonbroadcast | point-to-multipoint ]

Mode

Area Interface Configuration

Parameters

nonbroadcast - specifies a nonbroadcast interface on an NBMA medium

point-to-multipoint - specifies a point-to-multipoint interface

Description

Use the network command to specify either a nonbroadcast or point-to-point interface. Because an OSPF

broadcast medium must support IP multicasting, a broadcast-capable medium that does not support IP multicasting must be configured as a nonbroadcast interface. This includes the loopback interface on many operating systems.

no-multicast

Fast Open Shortest Path First (OSPF) Page 231

Default

The default mode is broadcast/point-to-point; therefore this command is not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures interface lo1 as a nonbroadcast interface in area 2.2.2.2.

(config)# interface lo1

(config-if)# ip ospf 1 area 2.2.2.2

(config-if-ip-ospf)# network nonbroadcast

(config-if-ip-ospf)# exit

(config-if)#

See Also

"ip ospf area" ("ip ospf area" on page 241)

no-multicast

Name

no-multicast - disables multicast on a specified interface

Syntax

no-multicast

no no-multicast

Mode

Area Interface Configuration

Parameters

none

Description

The no-multicast command explicitly disables multicast for an area on a specified interface. The

negative form of this command, no no-multicast, re-enables multicast on the area interface.

Default

By default, interfaces are multicast interfaces. Therefore, if no-multicast is not specified, it is the same

as if the user had specified the following:

(config-if-ip-ospf)# no no-multicast

Command History

NGC 2.3 - This command was introduced.

Examples

The following example disables multicast for area 2.2.2.2 on interface fxp2.

(config)# interface fxp2

(config-if)# ip ospf 1 area 2.2.2.2

passive-interface

Fast Open Shortest Path First (OSPF) Page 232

(config-if-ip-ospf)# no-multicast

(config-if-ip-ospf)# exit

(config-if)#

See Also

"ip ospf area" ("ip ospf area" on page 241)

passive-interface

Name

passive-interface - disables reception and transmission on an interface for a specific area

Syntax

passive-interface

no passive-interface

Mode

Area Interface Configuration

Parameters

none

Description

This command specifies that Advanced Routing Suite will neither send nor receive packets on this interface. This is used, for example, when this is the only router on the network. This has the effect of originating a stub link to his interface into the domain.

Note: OSPF passive interface is not used to learn other routers’ announcements, which is the way passive works in RIP. If your host is connected to a single network on which there are multiple routers, use Router Discovery combined with ICMP redirects to learn a default route and the best route. If your host is connected directly to multiple networks, this method might produce the best routes.

The negative form of this command, no passive-interface, re-enables reception and transmission for

an area on the interface.

Default

If passive-interface is not specified, it is the same as if the user had specified the following:

(config-if-ip-ospf)# no passive-interface

Command History

NGC 2.3 - This command was introduced.

Examples

The following example specifies to not send or receive packets on area 1.2.3.4 for interface fxp2.

(config)# interface fxp2

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# passive-interface

(config-if-ip-ospf)# exit

(config-if)#

poll-interval

Fast Open Shortest Path First (OSPF) Page 233

See Also

"ip ospf area" ("ip ospf area" on page 241)

poll-interval

Name

poll-interval - specifies the length of time, in seconds, between OSPF packets that the router send

before adjacency is established with a neighbor

Syntax

poll-interval time-seconds

no poll-interval time-seconds?

Mode

Area Interface Configuration

Parameters

time-seconds - the length of time in seconds, specified as an integer between 1 and 65535, inclusive

Description

The poll-interval command specifies the length of time, in seconds, between OSPF packets that the

router sends before adjacency is established with a neighbor. Utilizing this command reduces network overhead in cases where a router may have a neighbor on a given interface at the expense of initial convergence time.

The negative form of this command, no poll-interval, removes the configured time-seconds value and

returns this to its default value of 120 seconds. Note: Specifying a value for time-seconds in the no form has

no effect on the configuration. Thus, it is displayed above as optional.

Default

If poll-interval is not specified, it is the same as if the user had specified the following:

(config-if-ip-ospf)# poll-interval 120

Command History

NGC 2.3 - This command was introduced.

Examples

The following configures the poll-interval for area 1.2.3.4 on interface fxp0 to be 100 seconds.

(config)# interface fxp0

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# poll-interval 100

(config-if-ip-ospf)# exit

(config-if)#

See Also

"area poll-interval" ("area poll-interval" on page 208)

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf poll-interval" ("ip ospf poll-interval" on page 251)

"poll-interval" ("poll-interval" on page 184)

priority

Fast Open Shortest Path First (OSPF) Page 234

priority

Name

priority - configures the area-specific priority on an interface for becoming the designated router (DR)

Syntax

priority level

no priority level?

Mode

Area Interface Configuration

Parameters

level - a priority number between 0 and 255, inclusive, for becoming a DR

Description

The priority command configures the area-specific priority on this interface for becoming the DR. This

priority overrides any that is configured at the global or area levels. (See "priority" ("priority" on page 185) and "area priority" ("area priority" on page 209).) When more than one router attached to a network attempts to become the DR, the one with the highest priority wins. If the competing routers have the same priority, the one with the highest router ID becomes the DR. The router coming in second in the election becomes the backup DR. A router with a priority set to 0 is ineligible to become the DR.

The negative form of this command, no priority, removes the configured priority. Note: Specifying a

value for level in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Note: This command applies only to broadcast or NBMA media.

Default

If the priority command is not specified, then this value defaults to the configured area or global value,

respectively. If neither of those is configured, then this value defaults to the following:

(config-if-ip-ospf)# priority 1

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a global priority of 10. It also configures the priority for area 1.2.3.4 on interface fxp1 to be 5.

(config)# router ospf 1

(config-router-ospf)# priority 10

(config-router-ospf)# exit

(config)# interface fxp1

(config)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# priority 5

(config-if-ip-ospf)# exit

(config-if)#

See Also

"area priority" ("area priority" on page 209)

retransmit-interval

Fast Open Shortest Path First (OSPF) Page 235

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf priority" ("ip ospf priority" on page 252)

"priority" ("priority" on page 185)

retransmit-interval

Name

retransmit-interval - specifies the number of seconds between link state advertisement (LSA)

retransmissions for adjacencies

Syntax

retransmit-interval time-seconds

no retransmit-interval time-seconds?

Mode

Area Interface Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The retransmit-interval command sets the default for the number of seconds between LSA

retransmissions for adjacencies. If a Link State Protocol (LSP) is not acknowledged within the number of seconds specified here, it is re-sent.

This command overrides any configured in the global or area levels. (See "retransmit-interval" ("retransmit-interval" on page 193) and "area retransmit-interval" ("area retransmit-interval" on page 211).)

The negative form of this command, no retransmit-interval, removes the configured retransmit value.

Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

Default

If the retransmit-interval command is not specified, then this value defaults to the configured area or

global value, respectively. If neither of those is configured, then this value defaults to the following:

(config-if-ip-ospf)# retransmit-interval 5

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures the global retransmit interval f10 seconds. This value is then overridden in interface fxp1 for the area 1.2.3.4, where it is configured to be 7 seconds.

(config)# router ospf 1

(config-router-ospf)# retransmit-interval 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if-ip-ospf)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# retransmit-interval 7

(config-if-ip-ospf)# exit

traffic-eng administrative-weight

Fast Open Shortest Path First (OSPF) Page 236

(config-if)#

See Also

"area retransmit-interval" ("area retransmit-interval" on page 211)

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf retransmit-interval" ("ip ospf retransmit-interval" on page 253)

"retransmit-interval" ("retransmit-interval" on page 193)

traffic-eng administrative-weight

Name

traffic-eng administrative-weight - sets the area-specific cost of the interface for Traffic

Engineering purposes

Syntax

traffic-eng administrative-weight number

no traffic-eng administrative-weight number?

Mode

Area Interface Configuration

Parameters

number - an integer from 1 to 65535, inclusive

Description

Use the traffic-eng administrative-weight command to configure the cost of the interface for

Traffic Engineering purposes. This cost can be different than the normal OSPF interface cost. The negative

form of this command, no traffic-eng administrative-weight, removes the configured number

value.

Notes:

Specifying a value for number in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Traffic engineering must be enabled on the router before this command will take effect. See "enable-te" ("enable-te" on page 177).

Default

This command is not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a traffic engineering cost of 6 for area 1.2.3.4 on interface fxp2.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)# interface fxp2

(config-if)# ip ospf 1 area 1.2.3.4

traffic-eng attribute-flags

Fast Open Shortest Path First (OSPF) Page 237

(config-if-ip-ospf)# traffic-eng administrative-weight 6

(config-if-ip-ospf)# exit

(config)#

See Also

"enable-te" ("enable-te" on page 177)

"ip ospf area" ("ip ospf area" on page 241)

traffic-eng attribute-flags

Name

traffic-eng attribute-flags - sets the OSPF Traffic Engineering attributes for the interface

Syntax

traffic-eng attribute-flags number

no traffic-eng attribute-flags number?

Mode

Area Interface Configuration

Parameters

number - an integer from 0 to 4,294,967,295, inclusive

Description

Use the traffic-eng attribute-flags command to sets the area-specific OSPF Traffic Engineering

attributes for the interface. These flags can be used to indicate which link groups (or "colors") are present on

the interface. The negative form of this command, no traffic-eng attribute-flags, removes the

configured number value.

Notes:

Specifying a value for number in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Traffic engineering must be enabled on the router before this command will take effect. See "enable-te" ("enable-te" on page 177).

Default

This command is not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a traffic engineering attribute flag of 1 for area 1.2.3.4 on interface fxp2.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)# interface fxp2

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# traffic-eng attribute-flags 1

traffic-eng bandwidth

Fast Open Shortest Path First (OSPF) Page 238

(config-if-ip-ospf)# exit

(config-if)#

See Also

"enable-te" ("enable-te" on page 177)

"ip ospf area" ("ip ospf area" on page 241)

traffic-eng bandwidth

Name

traffic-eng bandwidth - sets the bandwidth of the interface

Syntax

traffic-eng bandwidth kbps

no traffic-eng bandwidth kbps

Mode

Area Interface Configuration

Parameters

kbps - an integer from 0 to 65535, inclusive, specifying a number of kilobytes per second

Description

The traffic-eng bandwidth command configures an area-specific bandwidth of the interface for Traffic

Engineering information distributed within the OSPF domain. The negative form of this command, no

traffic-eng bandwidth, removes the configured kbps value.

Notes:

Specifying a value for kbps in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Traffic engineering must be enabled on the router before this command will take effect. See "enable-te" ("enable-te" on page 177).

Default

This command is not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures a traffic engineering bandwidth of 1000 kbps for area 1.2.3.4 on interface fxp2.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)# interface fxp2

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# traffic-eng bandwidth 1000

(config-if-ip-ospf)# exit

transmit-delay

Fast Open Shortest Path First (OSPF) Page 239

(config-if)#

See Also

"enable-te" ("enable-te" on page 177)

"ip ospf area" ("ip ospf area" on page 241)

transmit-delay

Name

transmit-delay - specifies the number of seconds required to transmit a link state update

Syntax

transmit-delay time-seconds

no transmit-delay time-seconds?

Mode

Area Interface Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The transmit-delay command sets the estimated number of seconds required to transmit a link state

update. This command takes into account transmission and propagation delays and must be greater than 0. This command overrides any given at the global or area levels ("transmit-delay" ("transmit-delay" on page 198) and "area transmit-delay" ("area transmit-delay" on page 215)).

The negative form of this command, no transmit-delay, removes the configured time-seconds value.

Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

Default

If transmit-delay is not specified, then this value defaults to the configured area or global value,

respectively. If neither of those is configured, then this value defaults to the following:

(config-if-ip-ospf)# transmit-delay 1

Command History

NGC 2.3 - This command was introduced.

Examples

The following example configures the global transmit-delay for to be 10 seconds. This value is then overridden on interface fxp1 for area 1.2.3.4, where it is configured to be 5 seconds.

(config)# router ospf 1

(config-router-ospf)# transmit-delay 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)# transmit-delay 5

(config-if-ip-ospf)# exit

ip ospf advertise-subnet

Fast Open Shortest Path First (OSPF) Page 240

(config-if)#

See Also

"area transmit-delay" ("area transmit-delay" on page 215)

"ip ospf area" ("ip ospf area" on page 241)

"ip ospf transmit-delay" ("ip ospf transmit-delay" on page 256)

"transmit-delay" ("transmit-delay" on page 198)

ip ospf advertise-subnet

Name

ip ospf advertise-subnet - specifies whether OSPF will, when advertising point-to-point interfaces,

advertise the network number and netmask of the point-to-point interface instead of a host route to the remote IP

Syntax

ip ospf advertise-subnet

no ip ospf advertise-subnet

Mode

Interface Configuration

Parameters

none

Description

The ip ospf advertise-subnet command specifies whether OSPF will, when advertising point-to-point

interfaces, advertise the network number and netmask of the point-to-point interface instead of a host route to the remote IP. Because the netmask is sometimes set improperly on point-to-point interfaces, this option disabled by default.

Default

If ip ospf advertise-subnet is not specified, it is the same as if the user had specified the following:

(config-if)# no ip ospf advertise-subnet

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns advertise-subnet on for interface ppp0.

(config)# interface ppp0

(config-if)# ip ospf advertise-subnet

(config-if)# exit

(config)#

ip ospf allow-all

Fast Open Shortest Path First (OSPF) Page 241

ip ospf allow-all

Name

ip ospf allow-all - permits packets from all routers

Syntax

ip ospf allow-all

no ip ospf allow-all

Mode

Interface Configuration

Parameters

none

Description

The ip ospf allow-all command specifies to allow packets from all routers, including those not specified

in the "ip ospf neighbor" ("ip ospf neighbor" on page 248) command.

Default

If ip ospf allow-all is not specified, it is the same as if the user had specified the following:

(config-if)# no ip ospf allow-all

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that interface fxp1 will allow packets from all routers.

(config)# interface fxp1

(config-if)# ip ospf allow-all

(config-if)# exit

(config)#

ip ospf area

Name

ip ospf area - configures an area ID for an interface

Syntax

ip ospf instance_id area area_id

no ip ospf instance_id area area_id

Mode

Interface Configuration

ip ospf authentication

Fast Open Shortest Path First (OSPF) Page 242

Parameters

instance_id - specifies to return information for a specific instance. This can be an integer from 1 to

4,294,967,294, inclusive.

area_id - an ID for an area specified as either a decimal value or as an IP address in dotted-quad format. A

value of 0.0.0.0 signals that the area is a backbone.

Description

The ip ospf area command sets the OSPF area ID for an interface and enters the user into OSPF Area

Interface Configuration mode. As a result, all remaining interface attributes can be configured for this area.

Default

This command is not explicitly configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

In the following example, area 1.2.3.4 is configured for interface fxp1.

(config)# interface fxp1

(config-if)# ip ospf 1 area 1.2.3.4

(config-if-ip-ospf)#

ip ospf authentication

Name

ip ospf authentication - specify the type of authentication and key values for an interface

Syntax

ip ospf authentication [ [simple key] | [ md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time) || (start-accept date_time) (stop-accept date_time)]? ] ]

no ip ospf authentication [ simple key | md5 id_number ]

Mode

Interface Configuration

Parameters

simple key - specifies simple (clear password) authentication. The value for key is specified as a one- to

eight-character string.

md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time)

|| (start-accept date_time) || (stop-accept date_time)] - specifies the authentication

used for specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is a one- to sixteen-character string. The start and stop values must be in the format: YYYY-MM-DD.HH.MM. Each start and stop value is optional, and order is not important when specifying multiple commands.

Description

Authentication can help to guarantee that routing information is imported only from trusted routers. A variety of authentication schemes can be used, but a single scheme must be configured for each network. The use

ip ospf authentication

Fast Open Shortest Path First (OSPF) Page 243

of different schemes enables some interfaces to use much stricter authentication than others. The two authentication schemes available are simple, and MD5.

The ip ospf authentication command specifies the type of authentication and key values used on an

interface. This is used by OSPF authentication to generate and verify the authentication field in the OSPF header. If configured, the area authentication ("area authentication" ("area authentication" on page 200)) is the default unless it is configured here at the interface level.

When you want to keep certain routers from exchanging OSPF packets, use the simple form of authentication. The interfaces that the packets are to be sent on still need to be trusted, because the key will be placed in the packets and can be seen by anyone with access to the network.

When you do not trust other users of your network, use MD5 authentication. The system works by using shared secret keys. Because the keys are used to sign the packets with an MD5 checksum, they cannot be forged or tampered with. Because the keys are not included in the packet, snooping the key is not possible. Users of the network can still snoop the contents of packets, however, because the packets are not encrypted.

Advanced Routing Suite's MD5 authentication is compliant with the specification in OSPF RFC 2328. This specification uses the MD5 algorithm and an authentication key of up to 16 characters. RFC 2328 allows multiple MD5 keys per interface. Each key has two associated time ranges.

Note: In order to turn off authentication, you must include the authentication type in the no form of the

command. For example, if MD5 authentication was configured, then simply specifying no ip ospf

authentication will not work. In addition, you must specify the simple key when turning off simple

authentication, and you must specify the MD5 id_number when turning off MD5 authentication.

Default

Authentication is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the area authentication to be the simple keyword "abc". This authentication is then overridden for interface fxp0 to be "bar".

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 authentication simple abc

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf authentication simple bar

(config-if)# exit

(config)#

Example 2

The following example configures md5 authentication for interface fxp1. The ID for this md5 configuration is 1, and the key is configured as "bar".

(config)# interface fxp1

(config-if)# ip ospf authentication md5 1 bar

(config-if)# exit

(config)#

Example 3

The following example turns off the MD5 authentication that was configured in Example 2. Note that specifying the MD5 key is not required, but specifying the MD5 ID is.

ip ospf cost

Fast Open Shortest Path First (OSPF) Page 244

(config)# interface fxp1

(config-if)# no ip ospf authentication md5 1

(config-if)# exit

(config)#

Example 4

The following example configures md5 authentication for interface fxp3. The md5 authentication is configured with a start-generate time set to January 02, 2004 at 21:30 hours, a stop-generate time set to January 02, 2004 at 21:45 hours, a start-accept time set to January 02, 2004 at 21:00 hours, and a stop-accept time set to January 02, 2004 at 22:00 hours.

(config)# interface fxp3

(config-if)# ip ospf authentication md5 2 md5 start-generate 2004-01-02.21.30 stop-generate 2004-01-02.21.45 start-accept 2004-01-02.21.00 stop-accept 2004-01-02.22.00

(config-if)# exit

(config)#

See Also

"authentication" ("authentication" on page 172)

"area authentication" ("area authentication" on page 200)

ip ospf cost

Name

ip ospf cost - specifies the cost for a route to transmit an interface

Syntax

ip ospf cost cost_value

no ip ospf cost cost_value?

Mode

Interface Configuration

Parameters

cost_value - the cost to be associated with this interface, specified as an integer between 1 and 65535

Description

The ip ospf cost command is used for specifying the cost for a route to transmit an interface. This

command can be explicitly overridden in export policy. The negative form of this command, no ip ospf

cost, removes the configured cost and returns this to its default value of 1. Note: Specifying a value for

cost_value in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip ospf cost is not specified, it is the same as if the user had specified the following:

(config-if)# ip ospf cost 10

Command History

NGC 2.2 - This command was introduced.

ip ospf dead-interval

Fast Open Shortest Path First (OSPF) Page 245

Examples

The following example configures the cost for interface fxp1 to be 15.

(config)# interface fxp1

(config-if)# ip ospf cost 15

(config-if)# exit

(config)#

ip ospf dead-interval

Name

ip ospf dead-interval - specifies the number of seconds that may elapse on this interface without

receiving a router’s hello packets before the router’s neighbors will declare it down

Syntax

ip ospf dead-interval time-seconds

no ip ospf dead-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying an amount of time in seconds

Description

Use the ip ospf dead-interval command to specify the amount of time, in seconds, that can elapse

without receiving a router’s hello packets before the router’s neighbors will declare it down. This command is specified here at the interface level. It overrides a dead-interval configured at the area and global levels.

A general rule for configuring this value is that it should be equal to four times the HELLO interval. (See "ip ospf hello-interval" ("ip ospf hello-interval" on page 247).) Do not set this value to less than the HELLO interval because convergence will not occur.

The negative form of this command, no ip ospf dead-interval, removes the configured time-seconds

value and returns this to its default value of 40 seconds. Note: Specifying a value for time-seconds in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip ospf dead-interval is not specified, it defaults to the value specified in "area dead-interval" ("area

dead-interval" on page 202) then the global "dead-interval" ("dead-interval" on page 174). If neither of these is specified, however, then it is the same as if the user had specified the following:

(config-if)# ip ospf dead-interval 40

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a dead-interval of 80 seconds in area 1.2.3.4, and a dead-interval of 60 seconds on interface fxp1.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 dead-interval 80

(config-router-ospf)# exit

ip ospf enable

Fast Open Shortest Path First (OSPF) Page 246

(config)# interface fxp1

(config-if)# ip ospf dead-interval 60

(config-if)# exit

(config)#

See Also

"dead-interval" ("dead-interval" on page 174)

"area dead-interval" ("area dead-interval" on page 202)

ip ospf enable

Name

ip ospf enable - enables OSPF on an interface

Syntax

ip ospf enable

no ip ospf enable

Mode

Interface Configuration

Parameters

none

Description

The ip ospf enable command specifies to run OSPF on an interface.

Default

By default, OSPF runs on configured interfaces. Therefore, if ip ospf enable is not specified, it is the

same as if the user had specified the following:

(config-if)# ip ospf enable

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables interface fxp1.

(config)# interface fxp1

(config-if)# no ip ospf enable

(config-if)# exit

(config)#

ip ospf hello-interval

Fast Open Shortest Path First (OSPF) Page 247

ip ospf hello-interval

Name

ip ospf hello-interval - specifies the length of time in seconds between hello packets that the router

sends on the interface

Syntax

ip ospf hello-interval time-seconds

no ip ospf hello-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying an amount of time in seconds

Description

Use the ip ospf hello-interval command to specify the number of seconds between Hello packets

sent by the router on this interface. This command overrides the interval configured in the equivalent global and area commands. (See "hello-interval" ("hello-interval" on page 178) and "area hello-interval" ("area hello-interval" on page 204).)

A general rule for configuring this value is that it should be equal to one-fourth the dead interval. (See "ip ospf dead-interval" ("ip ospf dead-interval" on page 245).) This value should never be less than the dead interval value.

The negative form of this command, no ip ospf hello-interval, removes the configured time-seconds

value. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it

is displayed above as optional.

Default

If ip ospf hello-interval is not specified, it defaults to the value specified in "area hello-interval" ("area

hello-interval" on page 204) then in the global "hello-interval" ("hello-interval" on page 178). If neither the area nor global hello interval is specified, however, then it is the same as if the user had specified the following:

(config-if)# ip ospf hello-interval 10

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a hello interval of 20 seconds in area 1.2.3.4, and a hello interval of 15 seconds on interface fxp1.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 hello-interval 20

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf hello-interval 15

(config-if)# exit

(config)#

ip ospf neighbor

Fast Open Shortest Path First (OSPF) Page 248

See Also

"hello-interval" ("hello-interval" on page 178)

"area hello-interval" ("area hello-interval" on page 204)

ip ospf neighbor

Name

ip ospf neighbor - specifies neighboring routes, and specifies whether those routes are eligible to

become the designated router (DR)

Syntax

ip ospf neighbor ip_address [eligible]?

no ip ospf neighbor ip_address [eligible]?

Mode

Interface Configuration

Parameters

ip_address - a valid IPv4 address specified in dotted-quad notation

eligible - optionally specify whether the indicated address is eligible to become the DR

Description

By definition it is not possible to send broadcast or multicast packets to discover OSPF neighbors on a non-broadcast medium, so all neighbors must be configured. The host address list includes one or more

neighbors. The eligible option is used to indicate an address’s eligibility to become a DR. Refer to

section 9.5.1 of RFC 2328 for more information.

The negative form of this command, no ip ospf neighbor, removes the configured neighbors.

Default

OSPF neighbors are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies that host 10.1.1.1 is eligible to become a DR.

(config)# interface fxp1

(config-if)# ip ospf neighbor 10.1.1.1 eligible

(config-if)# exit

(config)#

ip ospf network

Name

ip ospf network - specifies a either a nonbroadcast interface on an NBMA medium or a

point-to-multipoint interface

ip ospf no-multicast

Fast Open Shortest Path First (OSPF) Page 249

Syntax

ip ospf network [ point-to-multipoint | nonbroadcast ]

no ip ospf network [ point-to-multipoint | nonbroadcast ]

Mode

Interface Configuration

Parameters

nonbroadcast - specifies a nonbroadcast interface on an NBMA medium

point-to-multipoint - specifies a point-to-multipoint interface

Description

Use the ip ospf network command to specify either a nonbroadcast or point-to-point interface. Because

an OSPF broadcast medium must support IP multicasting, a broadcast-capable medium that does not support IP multicasting must be configured as a nonbroadcast interface. This includes the loopback interface on many operating systems.

Default

The default mode is broadcast/point-to-point; therefore this command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures interface lo1 as a nonbroadcast interface.

(config)# interface lo1

(config-if)# ip ospf network nonbroadcast

(config-if)# exit

(config)#

ip ospf no-multicast

Name

ip ospf no-multicast - disables multicast on a specified interface

Syntax

ip ospf no-multicast

no ip ospf no-multicast

Mode

Interface Configuration

Parameters

none

Description

The ip ospf no-multicast command explicitly disables multicast on a specified interface. The negative

form of this command, no ip ospf no-multicast, re-enables multicast on an interface.

ip ospf passive-interface

Fast Open Shortest Path First (OSPF) Page 250

Default

By default, interfaces are multicast interfaces. Therefore, if ip ospf no-multicast is not specified, it is

the same as if the user had specified the following:

(config-if)# no ip ospf no-multicast

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables multicast on interface fxp2.

(config)# interface fxp2

(config-if)# ip ospf no-multicast

(config-if)# exit

(config)#

ip ospf passive-interface

Name

ip ospf passive-interface - disables reception and transmission on an interface

Syntax

ip ospf passive-interface

no ip ospf passive-interface

Mode

Interface Configuration

Parameters

none

Description

This command specifies that Advanced Routing Suite will neither send nor receive packets on this interface. This is used, for example, when this is the only router on the network. This has the effect of originating a stub link to his interface into the domain.

Note: OSPF passive interface is not used to learn other routers’ announcements, which is the way passive works in RIP. If your host is connected to a single network on which there are multiple routers, use Router Discovery combined with ICMP redirects to learn a default route and the best route. If your host is connected directly to multiple networks, this method might produce the best routes.

The negative form of this command, no ip ospf passive-interface, re-enables reception and

transmission on the interface.

Default

If ip ospf passive-interface is not specified, it is the same as if the user had specified the following:

(config-if)# no ip ospf passive-interface

Command History

NGC 2.2 - This command was introduced.

ip ospf poll-interval

Fast Open Shortest Path First (OSPF) Page 251

Examples

The following example specifies to not send or receive packets on interface fxp2.

(config)# interface fxp2

(config-if)# ip ospf passive-interface

(config-if)# exit

(config)#

ip ospf poll-interval

Name

ip ospf poll-interval - specifies the length of time, in seconds, between OSPF packets that the

router send before adjacency is established with a neighbor

Syntax

ip ospf poll-interval time-seconds

no ip ospf poll-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - the length of time in seconds, specified as an integer between 1 and 65535, inclusive

Description

The ip ospf poll-interval command specifies the length of time, in seconds, between OSPF packets

that the router sends before adjacency is established with a neighbor. Utilizing this command reduces network overhead in cases where a router may have a neighbor on a given interface at the expense of initial convergence time.

The negative form of this command, no ip ospf poll-interval, removes the configured time-seconds

value and returns this to its default value of 120 seconds. Note: Specifying a value for time-seconds in the

no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip ospf poll-interval is not specified, it is the same as if the user had specified the following:

(config-if)# ip ospf poll-interval 120

Command History

NGC 2.2 - This command was introduced.

Examples

The following configures the poll-interval for interface fxp0 to be 100 seconds.

(config)# interface fxp0

(config-if)# ip ospf poll-interval 100

(config-if)# exit

(config)#

See Also

"poll-interval" ("poll-interval" on page 184)

ip ospf priority

Fast Open Shortest Path First (OSPF) Page 252

"area poll-interval" ("area poll-interval" on page 208)

ip ospf priority

Name

ip ospf priority - specifies the priority for becoming the designated router (DR)

Syntax

ip ospf priority level

no ip ospf priority level?

Mode

Interface Configuration

Parameters

level - a priority number between 0 and 255, inclusive, for becoming a DR

Description

The ip ospf priority command specifies the priority on this interface for becoming the DR. This priority

overrides any that is configured at the global or area levels. (See "priority" ("priority" on page 185) and "area priority" ("area priority" on page 209).) When more than one router attached to a network attempts to become the DR, the one with the highest priority wins. If the competing routers have the same priority, the one with the highest router ID becomes the DR. The router coming in second in the election becomes the backup DR. A router with a priority set to 0 is ineligible to become the DR.

The negative form of this command, no ip ospf priority, removes the configured priority. Note:

Specifying a value for level in the no form has no effect on the configuration. Thus, it is displayed above as

optional.

Note: This command applies only to broadcast or NBMA media.

Default

If the ip ospf priority command is not specified, then this value defaults to the configured area or

global value, respectively. If neither of those is configured, then this value defaults to the following:

(config-if)# ip ospf priority 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures an area priority of 10. It also configures the priority for interface fxp1 to be 5.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 priority 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf priority 5

(config-if)# exit

(config)#

ip ospf retransmit-interval

Fast Open Shortest Path First (OSPF) Page 253

See Also

"priority" ("priority" on page 185)

"area priority" ("area priority" on page 209)

ip ospf retransmit-interval

Name

ip ospf retransmit-interval - specifies the number of seconds between link state advertisement

(LSA) retransmissions for adjacencies

Syntax

ip ospf retransmit-interval time-seconds

no ip ospf retransmit-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The ip ospf retransmit-interval command sets the default for the number of seconds between LSA

retransmissions for adjacencies. If a Link State Protocol (LSP) is not acknowledged within the number of seconds specified here, it is re-sent.

This command overrides any configured in the global or area levels. (See "retransmit-interval" ("retransmit-interval" on page 193) and "area retransmit-interval" ("area retransmit-interval" on page 211).)

The negative form of this command, no ip ospf retransmit-interval, removes the configured

retransmit value. Note: Specifying a value for time-seconds in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If the ip ospf retransmit-interval command is not specified, then this value defaults to the

configured area or global value, respectively. If neither of those is configured, then this value defaults to the following:

(config-if)# ip ospf retransmit-interval 5

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the retransmit interval for area 1.2.3.4 to be 10 seconds. This value is then overridden in interface fxp1, where it is configured to be 7 seconds.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 retransmit-interval 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf retransmit-interval 7

(config-if)# exit

ip ospf traffic-eng administrative-weight

Fast Open Shortest Path First (OSPF) Page 254

(config)#

See Also

"retransmit-interval" ("retransmit-interval" on page 193)

"area retransmit-interval" ("area retransmit-interval" on page 211)

ip ospf traffic-eng administrative-weight

Name

ip ospf traffic-eng administrative-weight - sets the cost of the interface for Traffic Engineering

purposes

Syntax

ip ospf traffic-eng administrative-weight number

no ip ospf traffic-eng administrative-weight number?

Mode

Interface Configuration

Parameters

number - an integer from 1 to 65535, inclusive

Description

Use the ip ospf traffic-eng administrative-weight command to configure the cost of the

interface for Traffic Engineering purposes. This cost can be different than the normal OSPF interface cost.

The negative form of this command, no ip ospf traffic-eng administrative-weight, removes the

configured number value.

Notes:

Specifying a value for number in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Traffic engineering must be enabled on the router before this command will take effect. See "enable-te" ("enable-te" on page 177).

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a traffic engineering cost of 6 on interface fxp2.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)# interface fxp2

(config-if)# ip ospf traffic-eng administrative-weight 6

See Also

"enable-te" ("enable-te" on page 177)

ip ospf traffic-eng attribute-flags

Fast Open Shortest Path First (OSPF) Page 255

ip ospf traffic-eng attribute-flags

Name

ip ospf traffic-eng attribute-flags - sets the OSPF Traffic Engineering attributes for the

interface

Syntax

ip ospf traffic-eng attribute-flags number

no ip ospf traffic-eng attribute-flags number?

Mode

Interface Configuration

Parameters

number - an integer from 1 to 4,294,967,295, inclusive

Description

Use the ip ospf traffic-eng attribute-flags command to sets the OSPF Traffic Engineering

attributes for the interface. These flags can be used to indicate which link groups (or "colors") are present on

the interface. The negative form of this command, no ip ospf traffic-eng attribute-flags,

removes the configured number value.

Notes:

Specifying a value for number in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Traffic engineering must be enabled on the router before this command will take effect. See "enable-te" ("enable-te" on page 177).

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a traffic engineering attribute flag of 1 on interface fxp2.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)# interface fxp2

(config-if)# ip ospf traffic-eng attribute-flags 1

See Also

"enable-te" ("enable-te" on page 177)

ip ospf traffic-eng bandwidth

Fast Open Shortest Path First (OSPF) Page 256

ip ospf traffic-eng bandwidth

Name

ip ospf traffic-eng bandwidth - sets the bandwidth of the interface

Syntax

ip ospf traffic-eng bandwidth kbps

no ip ospf traffic-eng bandwidth kbps

Mode

Interface Configuration

Parameters

kbps - an integer from 1 to 65535, inclusive, specifying a number of kilobytes per second

Description

The ip ospf traffic-eng bandwidth command configures the bandwidth of the interface for Traffic

Engineering information distributed within the OSPF domain. The negative form of this command, no ip

ospf traffic-eng bandwidth, removes the configured kbps value.

Notes:

Specifying a value for kbps in the no form has no effect on the configuration. Thus, it is displayed above

as optional.

Traffic engineering must be enabled on the router before this command will take effect. See "enable-te" ("enable-te" on page 177).

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a traffic engineering bandwidth of 1000 kbps for interface fxp2.

(config)# router ospf 1

(config-router-ospf)# enable-te

(config-router-ospf)# exit

(config)# interface fxp2

(config-if)# ip ospf traffic-eng bandwidth 1000

See Also

"enable-te" ("enable-te" on page 177)

ip ospf transmit-delay

Name

ip ospf transmit-delay - specifies the number of seconds required to transmit a link state update

show ip ospf

Fast Open Shortest Path First (OSPF) Page 257

Syntax

ip ospf transmit-delay time-seconds

no ip ospf transmit-delay time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - the length of time in seconds, between 1 and 65535, inclusive specified as an integer

Description

The ip ospf transmit-delay command sets the estimated number of seconds required to transmit a

link state update. This command takes into account transmission and propagation delays and must be greater than 0. This command overrides any given at the global or area levels ("transmit-delay" ("transmit-delay" on page 198) and "area transmit-delay" ("area transmit-delay" on page 215)).

The negative form of this command, no ip ospf transmit-delay, removes the configured time-seconds

value. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it

is displayed above as optional.

Default

If ip ospf transmit-delay is not specified, then this value defaults to the configured area or global

value, respectively. If neither of those is configured, then this value defaults to the following:

(config-if)# ip ospf transmit-delay 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the transmit-delay for area 1.2.3.4 to be 10 seconds. This value is then overridden on interface fxp1, where it is configured to be 5 seconds.

(config)# router ospf 1

(config-router-ospf)# area 1.2.3.4 transmit-delay 10

(config-router-ospf)# exit

(config)# interface fxp1

(config-if)# ip ospf transmit-delay 5

(config-if)# exit

(config)#

See Also

"transmit-delay" ("transmit-delay" on page 198)

"area transmit-delay" ("area transmit-delay" on page 215)

show ip ospf

Name

show ip ospf - displays information about a single OSPF instance or all OSPF instances

show ip ospf border-routers

Fast Open Shortest Path First (OSPF) Page 258

Syntax

show ip ospf instance_id?

Mode

User Execution

Parameters

instance_id - specifies to return information for a specific instance. This can be an integer from 1 to

4,294,967,294, inclusive. Entering this is optional.

Description

Use show ip ospf to obtain information about a specific OSPF instance or all OSPF instances.

This query has two forms. If the query is issued without an instance ID, then information on about all OSPF instances is returned. Alternatively, the query can be issued with a specific instance ID. If this is the case, then the reply will contain information pertaining only to that referenced instance.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example is a request for information relating to OSPF instance 2.

> show ip ospf 2

Routing Instance "2" with ID 192.168.10.1 RFC2328 Compliant RFC1583 mode is enabled

Configured as an area border and autonomous system boundary router Redistributing External Routes from: Static BGP Number of areas in this router is 1 Area 1.1.1.1 Number of interfaces in this area is 1 Configured as an NSSA area Area has simple password authentication SPF algorithm is executed 3 times default-cost is 5 nssa-translate-always is enabled nssa-translator-stability-interval is disabled area range is 192.10.0.0/24 default-metric is 10 default-nssa-type is 5

show ip ospf border-routers

Name

show ip ospf border-routers - displays the Autonomous System (AS) and Area Border Routers

(ABRs) for all OSPF instances

Syntax

show ip ospf border-routers

Mode

User Execution

show ip ospf database

Fast Open Shortest Path First (OSPF) Page 259

Parameters

none

Description

Use show ip ospf border-routers to display the AS and ABRs for all OSPF instances.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example is a request border router information.

> show ip ospf border-routers

OSPF Routing Table Route 192.168.10.1 area 0.0.0.1 ABR

show ip ospf database

Name

show ip ospf database - displays information contained within the OSPF Link State Database(s)

Syntax

show ip ospf database [instance_id]?

show ip ospf database instance_id area_id

Mode

User Execution

Parameters

instance_id - specifies to return information for a specific instance. This can be an integer from 1 to

4,294,967,294, inclusive. Entering this is optional.

area_id - if an instance ID is specified for a database, you can also optionally specify an area to be

associated with this query.

Description

The show ip ospf database query displays the information contained in the OSPF Link State

Database(s). This query can be narrowed to search a specific database, based on the instance ID, the area ID, whether to search the external database or the type-11-opaque database.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows a request for all OSPF database information.

> show ip ospf database

OSPF Router Instance 1

Router Link States (Area 0.0.0.1)

Link ID ADV RTR Seq No Age Checksum Link ct 192.168.10.0 192.168.1.8 0x80000003 0 0xBEEF 1

192.168.11.0 192.168.2.4 0x80000003 0 0xBEED 2

show ip ospf interface

Fast Open Shortest Path First (OSPF) Page 260

show ip ospf interface

Name

show ip ospf interface - displays information about a single or all interfaces running OSPF

Syntax

show ip ospf interface [instance_id interface-name]?

Mode

User Execution

Parameters

instance_id interface-name - optionally specify an instance ID along with a physical interface name to view

information for a specific interface

Description

Use show ip ospf interface to obtain information about a specific interface or all interfaces on which

OSPF is running.

This query has two forms. If the query is issued without arguments, then information on about all interfaces over which OSPF is running is returned. Alternatively, the query can be issued with a specific interface. If this is the case, then the reply will contain information pertaining only to that referenced interface. Note: When querying for a specific interface, you must first include the instance ID.

Note that if interfaces are added to the set of interfaces over which OSPF is running after this query has been issued but before the query is finished, it is not guaranteed that the new interfaces will be reported. Similarly, if OSPF is de-configured on an interface after the query has been issued but before the query is finished, then the interface may or may not be reported. Finally, if a machine is in idle state, OSPF interface information will not display.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns OSPF information for interface fxp0 in instance 1.

> show ip ospf interface 1 fxp0

fxp0 is up, line protocol is up Internet Address 192.168.10.1/24, Area 0.0.0.1 Router ID 192.168.10.5, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, state WAITING, Priority 1 Designated Router is 192.168.10.5 (this router) No Backup Designated router for this network Timer intervals configured, Hello 20, Dead, 120, Wait 30, Retransmit 5 Hello due in 0:00:05 Neighbor Count is 0, Adjacent neighbor count is 0

show ip ospf neighbor

Name

show ip ospf neighbor - displays information about OSPF neighbors

show ip ospf request-list

Fast Open Shortest Path First (OSPF) Page 261

Syntax

show ip ospf neighbor neighbor?

Mode

User Execution

Parameters

neighbor - optionally specify either a valid IPv4 address in dotted-quad notation or a physical interface

name for the OSPF neighbor on which to query information

Description

The show ip ospf neighbor query displays information about a single OSPF neighbor or all OSPF

neighbors.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns OSPF information for neighbor ID 2.2.2.2.

> show ip ospf neighbor 2.2.2.2

Routing Process "ospf 1": Neighbor 0.0.103.12, interface address 192.0.0.2 In area 0.0.0.2 interface "fxp0" Neighbor priority is 1, state is "Full", 7 state changes DR is 192.0.0.2 BDR is 192.0.0.1 Options is 0x2 Dead timer is due in 4 seconds

show ip ospf request-list

Name

show ip ospf request-list - displays a list of all LSAs requested by a router

Syntax

show ip ospf request-list [ neighbor | interface | interface_neighbor ]?

Mode

User Execution

Parameters

neighbor - optionally specify to display a list of all LSA requested by the router from this neighbor

interface - optionally specify to display a list of all LSAs requested by the router form this interface

interface_neighbor - optionally specify to display a list of all LSAs requested from this neighbor on this

interface

Description

The show ip ospf request-list query displays a list of all LSAs requested by a router.

show ip ospf retransmission-list

Fast Open Shortest Path First (OSPF) Page 262

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays a list of LSAs requested by the router for interface fxp0.

> show ip ospf request-list fxp0

OSPF Instance 1 Neighbor 192.168.10.5, interface fxp0 address 192.168.10.1

Type LS ID ADV RTR Seq No Age Checksum 1 192.168.10.9 192.168.10.9 0x80000001 35 0xBEEF

show ip ospf retransmission-list

Name

show ip ospf retransmission-list - displays a list of all LSAs waiting to be re-sent

Syntax

show ip ospf retransmission-list [ neighbor | interface | interface_neighbor ]?

Mode

User Execution

Parameters

neighbor - optionally specify to display a list of all LSA requested by the router from this neighbor

interface - optionally specify to display a list of all LSAs requested by the router form this interface

interface_neighbor - optionally specify to display a list of all LSAs requested from this neighbor on this

interface

Description

The show ip ospf retransmission-list query displays a list of all LSAs requested by a router that are

waiting to be re-sent.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays retransmission list information for interface fxp0.

> show ip ospf retransmission-list fxp0

OSPF Instance 1 Neighbor 192.168.10.5, interface fxp0 address 192.168.10.1 LSA retransmission due in 3000 msec, Queue length is 3

Type LS ID ADV RTR Seq No Age Checksum 1 192.168.10.9 192.168.10.9 0x80000001 35 0xBEEF

show ip ospf summary-address

Fast Open Shortest Path First (OSPF) Page 263

show ip ospf summary-address

Name

show ip ospf summary-address - displays information about configured OSPF area ranges

Syntax

show ip ospf summary-address

Mode

User Execution

Parameters

none

Description

Use show ip ospf summary-address to obtain information about configured OSPF area ranges.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example queries area range information.

> show ip ospf summary-address

OSPF Instance 1

192.168/20 Cost 0

show ip ospf virtual-links

Name

show ip ospf virtual-links - displays information about configured OSPF virtual links for a single

instance or for all OSPF instances

Syntax

show ip ospf virtual-links

Mode

User Execution

Parameters

none

Description

Use show ip ospf virtual-links to obtain information about configured OSPF virtual links.

Command History

NGC 2.2 - This command was introduced.

show ip ospf virtual-links

Fast Open Shortest Path First (OSPF) Page 264

Examples

The following example queries virtual link information.

> show ip ospf virtual-links

Virtual Link to router 192.168.101.2 is up Transit area 0.0.0.1 via interface fxp0 Link Cost is 5 Adjacency State is FULL Timer intervals configured, Hello 20, Dead 120, Wait 30 Retransmit 5 Hello due in 0:00:05

Page 265

Chapter 11

Redirect Processing

In This Chapter

Redirect Processing Overview 265

ip redirect 265

router redirect 266

trace file 266

trace flag 267

Redirect Processing Overview ICMP redirects are messages sent by a router to an originator of data, indicating that a different hop should be used to reach the destination. A router sends a redirect when a routing table lookup for a received datagram results in transmission of the datagram out the same interface on which it was received.

ip redirect

Name

ip redirect - specifies that redirects received via the specified interfaces will be ignored

Syntax

ip redirect enable

no ip redirect

Mode

Interface Configuration

Parameters

none

Description

Use the ip redirect command to specify that redirects received via the specified interface should be

ignore. The negative form of this command, no ip redirect, specifies that the redirects should be

accepted.

Default

Redirects are accepted by default. Therefore, if ip redirect is not specified, it is the same as if the user

had specified the following:

(config-if)# ip redirect enable

Command History

NGC 2.3 - This command was introduced.

router redirect

Redirect Processing Page 266

Examples

The following example specifies to ignore redirects on interface fxp1.

(config)# interface fxp1

(config-if)# no ip redirect

(config-if)# exit

(config)#

router redirect

Name

router redirect - configures the Redirect protocol on the router

Syntax

router redirect

no router redirect

Mode

Global Configuration

Parameters

none

Description

Use the router redirect command to configure the Redirect protocol on the router. This also enters the

user into Redirect Configuration mode, where tracing options can be specified. The negative form of this

command, no router redirect, turns off the Redirect protocol.

Default

If router redirect is not specified, it is the same as if the user had specified the following:

(config)# no router redirect

Command History

NGC 2.3 - This command was introduced.

Examples

The following example specifies to ignore redirects on interface fxp1.

(config)# router redirect

(config-router-redirect)# exit

(config)#

trace file

Name

trace file - specifies the file to receive tracing information, the size of the file, whether to overwrite

existing files, and the maximum number of files allowed

trace flag

Redirect Processing Page 267

Syntax

trace file file_name [no-timestamp || overwrite]?

no trace file file_name [no-timestamp || overwrite]?

Mode

Redirect Router Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For Redirect, the trace file command in Redirect Router

Configuration Mode specifies a file for tracing of all Redirect events. The negative form of this command

disables this tracing. The specific events that are traced are controlled by the trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands.

Default

Redirect tracing options are not configured by default.

Command History

NGC 2.3 - This command was introduced.

Examples

In the following example, tracing is written to the file "rdirct.log". No timestamp will display at the beginning of the trace lines.

(config)# router redirect enable

(config-router-redirect)# trace file rdirct.log no-timestamp

trace flag

Name

trace flag - specifies redirect tracing options

Syntax

trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ other | packets ] [receive]? [detail?] )

no trace flag ( [ route | normal | state | policy | task | timer | all ) | ( [ other | packets ] [receive]? [detail?] )

Mode

Redirect Router Configuration

trace flag

Redirect Processing Page 268

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

Redirect-specific flags:

[ other | packets ] - These Redirect-specific flags can be associated with the receive and detail action

items. These flags are defined as follows:

other - trace all other Redirect messages.

packets - trace all Redirect packets

[receive]? - optionally specify whether to limit the tracing to received packets

[detail]? - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the trace flag command to specify Redirect tracing flags. Each flag must reside on its own

configuration line. For example, you cannot specify to trace both task and policy packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.3 - This command was introduced.

Examples

In the following example, flags specify to trace both timer usage and state machine transition. This tracing information will be written to the file rdirct.log.

(config)# router redirect enable

(config-router-redirect)# trace file rdirct.log

(config-router-redirect)# trace flag timer

(config-router-redirect)# trace flag state

Page 269

Chapter 12

Router Discovery

In This Chapter

Router Discovery Overview 269

ip router-discovery address-policy 270

ip router-discovery enable 271

ip router-discovery trace file 271

ip router-discovery trace flag 272

router-discovery lifetime 273

router-discovery maximum-interval 274

router-discovery minimum-interval 275

Router Discovery Overview The Router Discovery Protocol is an IETF standard protocol (RFC 1256) used to inform hosts of the existence of routers. It is intended to be used instead of having hosts wiretap routing protocols, such as RIP. It is used in place of, or in addition to, statically-configured default routes in hosts. RFC 1256 can be found at: http://ietf.org/rfc/rfc1256.txt. The protocol is split into two portions: the server portion, which runs on routers, and the client portion, which runs on hosts. Advanced Routing Suite currently supports only the server configuration.

The router discovery server runs on routers and announces their existence to hosts by periodically multicasting or broadcasting a router advertisement to each interface on which it is enabled. These router advertisements contain a list of all the routers' addresses on a given interface and the preference of each address for use as the default router on that interface.

Initially, these router advertisements occur every few seconds, then fall back to every few minutes. In addition, a host can send a router solicitation to which the router will respond with a unicast router advertisement (unless a multicast or broadcast advertisement is due momentarily).

Each router advertisement contains an advertisement "lifetime", indicating for how long the advertised addresses are valid. This lifetime is configured such that another router advertisement will be sent before the lifetime has expired. A lifetime of zero is used to indicate that one or more addresses are no longer valid.

On systems supporting IP multicasting, the router advertisements are, by default, sent to the all-hosts

multicast address, 224.0.0.1. However, an advertisement method of broadcast can be specified. When

router advertisements are being sent to the all-hosts multicast address, or an interface is configured for the

limited-broadcast address, 255.255.255.255, all IP addresses configured on the physical interface are

included in the router advertisement. When the router advertisements are being sent to a net or subnet broadcast, only the address associated with that net or subnet is included.

A host listens for router advertisements via the all-hosts multicast address (224.0.0.1) if IP multicasting is

available and enabled, or on the interface's broadcast address. When starting up, or when reconfigured, a

host can send a few router solicitations to the all-routers multicast address, 224.0.0.2, or the interface's

broadcast address.

When a router advertisement with non-zero lifetime is received, the host installs a default route to each of the advertised addresses. If the preference is ineligible, or the address is not on an attached interface, the route is marked unusable but is retained. If the preference is usable, the metric is set as a function of the preference such that the route with the best preference is used. If more than one address with the same preference is received, the one with the lowest IP address will be used. These default routes are not exportable to other protocols.

ip router-discovery address-policy

Router Discovery Page 270

When a router advertisement with a zero lifetime is received, the host deletes all routes with next-hop addresses learned from that router. In addition, any routes learned from ICMP redirects pointing to these addresses will be deleted. The same will happen when a router advertisement is not received to refresh these routes before the lifetime expires.

ip router-discovery address-policy

Name

ip router-discovery address-policy - specifies policy-related parameters when configuring logical

interface addresses in router discovery.

Syntax

ip router-discovery address-policy ipv4_address [ (method (broadcast | ignore | multicast)) | (preference pref) | ineligible]

no ip router-discovery address-policy ipv4_address

Mode

Global Configuration

Parameters

ipv4_address - a valid IPv4 address in dotted-quad notation

method (multicast | broadcast | ignore) - optionally specify whether the associated IPv4 address

should be included in router advertisements and whether the router advertisements should be unicast or multicast. If ignore is specified, then the associated IPv4 address will not be included in router advertisements. Note: If an interface does not support multicast, but multicast is specified for that interface, then that interface will not be advertised.

preference pref - configures the preferability of the address as a default router address. Otherwise,

you can specify a value for pref between 1 and 255. The default preference value is 55.

ineligible - optionally specify that the router should be advertised with the worst possible preference,

making it ineligible to become the default router

Description

Use the ip router-discovery address-policy command to specify the logical interface or interfaces

that should be advertised in router advertisements. This command can be given multiple times, creating multiple interfaces to be advertised in router advertisements.

Default

The ip router-discovery address-policy command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the logical interface 223.1.5.8 with an advertisement method of broadcast and a preference of 10.

(config)# ip router-discovery address-policy 223.1.5.8 method broadcast preference 10

(config)#

ip router-discovery enable

Router Discovery Page 271

Example 2

The following example configures the logical interface 224.5.5.5 with an advertisement method of multicast. This interface is then configured such that it is ineligible to become the default router.

(config)# ip router-discovery address-policy 224.5.5.5 method multicast ineligible

(config)#

ip router-discovery enable

Name

ip router-discovery enable - enables the Router Discovery server

Syntax

ip router-discovery enable

no ip router-discovery enable

Mode

Global Configuration

Parameters

none

Description

Use the ip router-discovery enable command to enable Router Discovery on the server. The

negative form of this command disables Router Discover on the server.

Default

If ip router-discovery enable is not specified, it is the same as if the user had specified the following: (config)# ip router-discovery enable

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns Router Discovery off on the server

(config)# no ip router-discovery enable

(config)#

ip router-discovery trace file

Name

ip router-discovery trace file - specifies the file to receive tracing information, the size of the file,

whether to overwrite existing files, and the maximum number of files allowed

Syntax

ip router-discovery trace file file_name [no-timestamp || overwrite]?

no ip router-discovery trace file file_name [ no-timestamp ||overwrite]?

ip router-discovery trace flag

Router Discovery Page 272

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For Router Discovery, the ip router-discovery trace file

command specifies a file for tracing of all Router Discovery events. The negative form of this command

disables this tracing. The specific events that are traced are controlled by the ip router-discovery

trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands.

Default

Router Discovery tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, Router Discovery tracing is written to the file "rdisc.log". No timestamp will

display at the beginning of the trace lines.

(config)# ip router-discovery trace file rdisc.log no-timestamp

ip router-discovery trace flag

Name

ip router-discovery trace flag - specifies tracing options that are common across all protocols

Syntax

ip router-discovery trace flag ( [ route | normal | state | policy | task | timer | all ] )

no ip router-discovery trace flag ( [ route | normal | state | policy | task | timer | all ] )

Mode

Global Configuration

Parameters

Flags common to all protocols:

router-discovery lifetime

Router Discovery Page 273

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

Description

Use the ip router-discovery trace flag command to specify tracing flags for Router Discovery

tracing. Each flag must reside on its own configuration line. For example, you cannot specify to trace both task and policy packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, flags specify to trace state machine transitions. This tracing information will be

written to the file rdisc.log.

(config)# ip router-discovery trace file rdisc.log

(config)# ip router-discovery trace flag state

router-discovery lifetime

Name

router-discovery lifetime - specifies the length of time that the addresses in a given router

advertisement are valid

Syntax

router-discovery lifetime time-seconds

no router-discovery lifetime time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - specifies the length of time, in seconds, with a value between the Maximum

Advertisement Interval value (which has a minimum value of 4) and 9,000, inclusive

router-discovery maximum-interval

Router Discovery Page 274

Description

The router-discovery lifetime command specifies how long the addresses in a given router

advertisement are valid. Lifetime must be no less than "router-discovery maximum-interval" ("router-discovery maximum-interval" on page 274) and no more than 2 hours and 30 minutes. If this value is set to less than the Maximum Advertisement Interval, then Advanced Routing Suite will reconfigure

router-discovery lifetime to be equal to the Maximum Advertisement Interval.

The negative form of this command, no router-discovery lifetime, removes the configured

time-seconds value and returns this to its default value. Note: Specifying a value for time-seconds in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If router-discovery lifetime is not specified, it will default to 3 times the value of the Maximum

Advertisement Interval. Therefore, if neither value is configured, then the router-discovery lifetime

will default to: (config-if)# router-discovery lifetime 1800

Command History

NGC 2.2 - This command was introduced.

Examples

The following example runs the router discovery server on interface fxp0. All routers that it advertises out of interface fxp0 will be advertised with a lifetime of 10 minutes.

(config)# interface fxp0

(config-if)# router-discovery lifetime 1800

(config-if)# exit

(config)#

See Also

"router-discovery maximum-interval" ("router-discovery maximum-interval" on page 274)

"router-discovery minimum-interval" ("router-discovery minimum-interval" on page 275)

router-discovery maximum-interval

Name

router-discovery maximum-interval - specifies the maximum time allowed between sending

unsolicited router advertisements from the interface

Syntax

router-discovery maximum-interval time-seconds

no router-discovery maximum-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - specifies the length of time, in seconds, with a value between 4 and 1800, inclusive

router-discovery minimum-interval

Router Discovery Page 275

Description

The router-discovery maximum-interval command specifies the maximum time allowed between

sending unsolicited router advertisements from the interface. This must be no less than 4 seconds and no more than 30 minutes (1800 seconds).

The negative form of this command, no router-discovery maximum-interval, removes the

configured time-seconds value and returns this to its default value of 600 seconds. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If router-discovery maximum-interval is not specified, it is the same as if the user had specified the

following: (config-if)# router-discovery maximum-interval 600

Command History

NGC 2.2 - This command was introduced.

Examples

The following example runs the router discovery server on interface fxp0, sending advertisements no more

often than once every 6 minutes.

(config)# interface fxp0

(config-if)# router-discovery maximum-interval 360

(config-if)# exit

(config)#

See Also

"router-discovery lifetime" ("router-discovery lifetime" on page 273)

"router-discovery minimum-interval" ("router-discovery minimum-interval" on page 275)

router-discovery minimum-interval

Name

router-discovery minimum-interval - specifies the minimum time allowed between sending

unsolicited router advertisements from the interface

Syntax

router-discovery minimum-interval time-seconds

no router-discovery minimum-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - specifies the length of time, in seconds, with a value between 3 and "router-discovery

maximum-interval" ("router-discovery maximum-interval" on page 274) (which has a maximum value of 1800), inclusive

Description

The router-discovery minimum-interval command specifies the minimum time allowed between

sending unsolicited router advertisements from the interface. This must be no less than 3 seconds and no more than the "router-discovery maximum-interval" ("router-discovery maximum-interval" on page 274)

router-discovery minimum-interval

Router Discovery Page 276

value. If this value is set to greater than the Maximum Advertisement Interval, Advanced Routing Suite will reconfigure the value of the Minimum Advertisement Interval to be equal to the value of the Maximum Advertisement Interval log the change.

The negative form of this command, no router-discovery minimum-interval, removes the

configured time-seconds value and returns this to its default value. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If router-discovery minimum-interval is not specified, it will default to 3/4 the value of the Maximum

Advertisement Interval. Therefore, if neither value is configured, then the router-discovery

minimum-interval will default to: (config-if)# router-discovery minimum-interval 450

Command History

NGC 2.2 - This command was introduced.

Examples

The following example runs the router discovery server on interface fxp0, sending advertisements no less often than once every minute.

(config)# interface fxp0

(config-if)# router-discovery minimum-interval 60

(config-if)# exit

(config)#

See Also

"router-discovery lifetime" ("router-discovery lifetime" on page 273)

Page 277

Chapter 13

Routing Information Protocol (RIP)

In This Chapter

Routing Information Protocol (RIP) Overview 277

router rip 280

default-metric 280

distribute-list 281

ecmp 284

enable 284

flash-update-time 285

ignore-host-routes 286

ignore-must-be-zero 287

network 287

preference 288

query-authentication 289

redistribute 290

send-updates 292

source-gateways 294

split-horizon 295

term-updates 296

timers basic 297

trace file 298

trace flag 299

trusted-gateways 300

ip rip authentication 302

ip rip enable 303

ip rip metric-in 304

ip rip metric-out 305

ip rip no-receive 305

ip rip no-send 306

ip rip secondary-authentication 307

ip rip version 308

show ip rip database 309

Routing Information Protocol (RIP) Overview

One of the most widely used interior gateway protocols is the Routing Information Protocol (RIP). RIP is an implementation of a distance-vector, or Bellman-Ford, algorithm. RIP classifies routers as active and passive (silent). Active routers advertise their routes (reachability information) to others; passive routers listen and update their routes based on advertisements, but do not advertise. Typically, routers run RIP in active mode, while hosts use passive mode.

Routing Information Protocol (RIP) Overview

Routing Information Protocol (RIP) Page 278

A router running RIP in active mode sends updates at set intervals. Each update contains paired values, where each pair consists of an IP network address and an integer distance to that network. RIP uses a hop count metric to measure the distance to a destination. In the RIP metric, a router advertises directly connected networks at a metric of 1 by default. Networks that are reachable through one other gateway are 2 hops, etc. Thus, the number of hops or hop count along a path from a given source to a given destination refers to the number of gateways that a datagram would encounter along that path. Using hop counts to calculate shortest paths does not always produce optimal results. For example, a path with a hop count 3 that crosses three Ethernets may be substantially faster than a path with a hop count 2 that crosses two slow-speed serial lines. To compensate for differences in technology, many routers advertise artificially high hop counts for slow links.

RIP dynamically builds on information received through RIP updates. When started up, RIP issues a request for routing information and then listens for responses to the request. If a system configured to supply RIP hears the request, it responds with a response packet based on information in its routing database. The response packet contains destination network addresses and the routing metric for each destination.

When a RIP response packet is received, the routing daemon takes the information and rebuilds the routing database, adding new routes and "better" (lower metric) routes to destinations already listed in the database. RIP also deletes routes from the database if the next router to that destination reports that the route contains more than 15 hops, or if the route is deleted. All routes through a gateway are deleted if no updates are received from that gateway for a specified time period. In general, routing updates are issued every 30 seconds. In many implementations, if a gateway is not heard from for 180 seconds, all routes from that gateway are deleted from the routing database. This 180-second interval also applies to deletion of specific routes.

RIP version 2 (more commonly known as RIP II) adds additional capabilities to RIP. Some of these capabilities are compatible with RIP I and some are not. To avoid supplying information to RIP I routes that could be misinterpreted, RIP II can use only non-compatible features when its packets are multicast. On interfaces that are not capable of IP multicast, RIP-I-compatible packets are used that do not contain potentially confusing information.

Some of the most notable RIP II enhancements are:

Next hop

Network mask

Authentication

RIP tag field

These features in RIP I and II are contrasted in the following paragraphs.

Next hop

With RIP II, a router can advertise a next hop other than itself. Next hop is useful when advertising a static route to a dumb router that does not run RIP, because it avoids having packets that are passed through the dumb router from having to cross a network twice. Because RIP I routers will ignore next hop information in RIP II packets, packets might cross a network twice, which is exactly what happens with RIP I. Next hop information is provided in RIP-I-compatible RIP II packets.

Network mask

RIP I assumes that all subnetworks of a given network are classful (Class A,B,C). RIP I uses this assumption to calculate the network masks for all routes received. This assumption prevents subnets with classless netmasks from being included in RIP packets. RIP II adds the ability to specify the network mask with each network in a packet. Because RIP I routers will ignore the network mask in RIP II packets, their calculation of the network mask will quite possibly be wrong. For this reason, RIP-I-compatible RIP II packets must not contain networks that would be misinterpreted. These networks must be provided only in native RIP II packets that are multicast.

RIP I derives the network mask of received networks and hosts from the network mask of the interface via which the packet was received. If a received network or host is on the same natural network as the interface over which it was received, and that network is subnetted (the specified mask is more or less specific than the natural netmask), the interface’s subnet mask is applied to the destination. If bits outside the mask are set, it is assumed to be a host; otherwise, it is assumed to be a subnet. On point-to-point interfaces, the netmask is applied to the remote address. The netmask on these interfaces is ignored if it matches the natural network of the remote address, or is all ones. Unlike previous releases, the zero subnet (a

Routing Information Protocol (RIP) Overview

Routing Information Protocol (RIP) Page 279

subnetwork that matches the natural network of the interface, but has a more specific, or longer, network mask) is advertised. If this is not desirable, a route filter may be used to reject it.

Authentication

RIP II packets may contain one of two types of authentication strings that may be used to verify the validity of the supplied routing data. Authentication may be used in RIP-I-compatible RIP II packets, but be aware

that RIP I routers will ignore these packets (unless ignore-must-be-zero is configured off). The first

method is a simple password in which an authentication key of up to 16 characters is included in the packet. If this key does not match what is expected, the packet will be discarded. This method provides very little security because it is possible to learn the authentication key by watching RIP packets.

The second method uses the MD5 algorithm to create a crypto-checksum of a RIP packet and an authentication key of up to 16 characters. The transmitted packet does not contain the authentication key itself; instead, it contains a crypto-checksum, called the "digest". The receiving router will perform a calculation using the correct authentication key and discard the packet if the digest does not match. In addition, a sequence number is maintained to prevent the replay of older packets. This method provides a much stronger assurance that routing data originated from a router with a valid authentication key.

Two authentication methods can be specified per interface. Packets are always sent using the primary method, but received packets are checked with both the primary and secondary methods before being discarded. In addition, a separate authentication key is used for non-router queries.

RIP Commands

Global Configuration Mode RIP Commands

"router rip" ("router rip" on page 280)

Router Mode RIP Commands

"default-metric" ("default-metric" on page 280)

"distribute-list" ("distribute-list" on page 281)

"ecmp" ("ecmp" on page 284)

"enable" ("enable" on page 284)

"flash-update-time" ("flash-update-time" on page 285)

"ignore-host-routes" ("ignore-host-routes" on page 286)

"ignore-must-be-zero" ("ignore-must-be-zero" on page 287)

"network" ("network" on page 287)

"preference" ("preference" on page 288)

"query-authentication" ("query-authentication" on page 289)

"redistribute" ("redistribute" on page 290)

"send-updates" ("send-updates" on page 292)

"source-gateways" ("source-gateways" on page 294)

"split-horizon" ("split-horizon" on page 295)

"term-updates" ("term-updates" on page 296)

"timers basic" ("timers basic" on page 297)

"trace file" ("trace file" on page 298)

"trace flag" ("trace flag" on page 299)

"trusted-gateways" ("trusted-gateways" on page 300)

RIP Interface Commands

"ip rip authentication" ("ip rip authentication" on page 302)

"ip rip enable" ("ip rip enable" on page 303)

"ip rip metric-in" ("ip rip metric-in" on page 304)

router rip

Routing Information Protocol (RIP) Page 280

"ip rip metric-out" ("ip rip metric-out" on page 305)

"ip rip no-receive" ("ip rip no-receive" on page 305)

"ip rip no-send" ("ip rip no-send" on page 306)

"ip rip secondary-authentication" ("ip rip secondary-authentication" on page 307)

"ip rip version" ("ip rip version" on page 308)

RIP Querying Commands

"show ip rip database" ("show ip rip database" on page 309)

"show ip rip gateway-summary"

router rip

Name

router rip - enters the user into Router Configuration mode for RIP

Syntax

router rip

no router rip

Mode

Global Configuration

Parameters

none

Description

Use the router rip command to enter RIP Router Configuration mode. Once you are in RIP Router

Configuration mode, you can begin configuring RIP.

Default

None. You must specify this command in order to configure RIP.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows how to enter RIP Router Configuration mode.

(config)# router rip

(config-router-rip)#

default-metric

Name

default-metric - configures the default metric for advertising RIP routes learned from other protocols

distribute-list

Routing Information Protocol (RIP) Page 281

Syntax

default-metric metric_value

no default-metric metric_value?

Mode

RIP Router Configuration

Parameters

metric_value - an integer from 0 to 16, inclusive, assigned to exported reachability

Description

Use the default-metric command to set the default metric value for advertising RIP routes learned from

other protocols. All routes exported into RIP will receive this metric unless a matching route-map sets the metric to a different value.

The negative form of this command, no default-metric, removes the configured value and returns this

to its default value of 1. Note: Specifying a value for metric_value in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If default-metric is not specified, it is the same as if the user had specified the following:

(config-router-rip)# default-metric 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the RIP default metric value to be 2.

(config)# router rip

(config-router-rip)# default-metric 2

(config-router-rip)# exit

(config)#

distribute-list

Name

distribute-list - configures policy for RIP to apply to incoming or outgoing updates

Syntax

distribute-list access_list_name [in [interface-name || route-map rm_name]?] | [out [interface-name || protocol]? ]

no distribute-list access_list_name [in [interface-name || route-map rm_name]?] | [out [interface-name || protocol]?]

Mode

RIP Router Configuration Mode

distribute-list

Routing Information Protocol (RIP) Page 282

Parameters

distribute-list in

access_list_name - the name of an access list

in - specifies that the policy applies to incoming updates

interface-name - optionally specify a physical interface name to which this policy will apply. Otherwise, it applies to all interfaces.

route-map name - the name of a route map to apply to incoming routes. Specifying this is optional.

distribute-list out

access_list_name - the name of an access list

out - specifies that the policy applies to exported updates

interface-name - optionally specify a physical interface name to which this policy will apply. Otherwise, it applies to all interfaces.

protocol - optionally specify a redistributed protocol to filter. Valid values include: aggregate, bgp, isis,

kernel, ospf, ospf-ase, rip, and static.

Description

The distribute-list command provides a policy filtering mechanism for RIP routes. If the distribute list

configured in this command is specified with the in keyword, then the filter will apply to all imported routes

(that is to say, routes learned from RIP neighbors). If the distribute list configured in this command is

specified with the out keyword, then the filter applies to exported routes (that is to say, routes announced to

RIP neighbors).

To delete a configured distribute list, use the negative form of the command. Note: All arguments of the original command must be supplied in order for the entry to be deleted.

distribute-list in

The distribute-list in command configures a RIP import policy (in other words, a policy for RIP to

apply to incoming updates). You can specify both an interface-name and a Route Map in the policy. Note that order is not important when specifying both.

If an inbound distribute-list is configured, then each route received from other RIP neighbors will be

evaluated against this inbound list. If the route matches the criteria specified by the inbound list, then the route is imported. If the route does not match the inbound list criteria, then the route is rejected. A route matches the inbound list criteria if it is permitted when evaluated against the referenced access list.

Furthermore, if the inbound distribute-list references a route map, then the route must also match

when evaluated against the route map.

If the distribute-list in command references a route map that has not yet been defined, then an

empty route map is created with the specified name.

If two inbound distribute lists are configured, one that does not reference an interface and one that does, then the most specific inbound distribute list is used when evaluating a route received from other RIP neighbors. If the route was received over an interface not named in any inbound distribute list, then the inbound distribute list that does not reference an interface is used. Otherwise, the inbound distribute list that references the interface over which the route was received is used.

At most, one distribute-list in command can be specified without an interface. Subsequent

distribute-list in commands that do not reference an interface will overwrite any such previous

command. Similarly, at most one distribute-list in command can be specified for each interface, and

subsequent commands that reference an interface will overwrite any such previous command.

distribute-list out

The distribute-list out command is used to configure export policy for RIP routes. Outbound

distribute lists look similar to inbound distribute lists, except that they allow you to optionally specify an interface and a protocol, or more correctly, a route source. This allows you to filter exported routes based on whether they were learned from BGP, OSPF, OSPF-ASE or were aggregate, static, or kernel routes. If an

distribute-list

Routing Information Protocol (RIP) Page 283

interface is specified, then the export policy described by the distribute-list out command only applies to the

referenced interface. At most one distribute-list out command can be specified for each interface for

each protocol. Furthermore, at most one distribute-list out command that does not reference a

protocol can be specified. If an outbound distribute list is configured without referencing a protocol, then when a route is being considered for export to RIP neighbors, it must be permitted by the access list referenced in the distribute list. If instead an outbound distribute list is configured that references a protocol, and if the route being considered for export originated from the referenced protocol, then the route must be permitted by the access list referenced in the distribute list. If more of both types of lists are present, then the route need only be permitted by the access list referenced by one of the outbound distribute lists.

It should be noted that an outbound distribute list has no effect in the absence of a "redistribute" ("redistribute" on page 290) command. Outbound distribute lists can be thought of as a way to further refine the export policy expressed with a "redistribute" ("redistribute" on page 290) command.

The negative form of this command, no distribute-list, removes the configured list. You must

specify either in or out in the negative form. For outbound distribute lists, specifying a protocol is optional.

If the protocol is not specified, then all distribute lists referencing the specified access list will be deleted.

Default

The default is for RIP to import everything.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

In the following example, incoming updates received on interface fxp0 are matched against a standard IP access-list named "abc".

(config)# router rip

(config-router-rip)# distribute-list abc in fxp0

(config-router-rip)# exit

(config)#

Example 2

In the following example, incoming updates received on interface fxp0 are matched against a standard IP access-list named "alist1". A route map named "rm1" is also applied to the incoming updates.

(config)# router rip

(config-router-rip)# distribute-list alist1 in route-map rm1 fxp0

(config-router-rip)# exit

(config)#

Example 3

In the following example, incoming updates from all interfaces are matched against a standard IP access-list named "alist1". A route map named "rm1" is also applied to incoming updates.

(config)# router rip

(config-router-rip)# distribute-list alist1 in route-map rm1

(config-router-rip)# exit

(config)#

Example 4

In the following example, the distribute-list entry originally configured in Example 3 is deconfigured.

(config)# router rip

ecmp

Routing Information Protocol (RIP) Page 284

(config-router-rip)# no distribute-list alist1 in route-map rm1

(config-router-rip)# exit

(config)#

ecmp

Name

ecmp - configures equal-cost multipaths

Syntax

ecmp

no ecmp

Mode

RIP Router Configuration

Parameters

none

Description

The ecmp command is used to enable the Equal-Cost Multi-Path (ECMP) feature. Use the negative form of

this command, no ecmp, to disable the ECMP feature.

Default

If ecmp is not specified, it is the same as if the user had specified the following:

(config-router-rip)# no ecmp

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns on the ECMP feature.

(config)# router rip

(config-router-rip)# ecmp

(config-router-rip)# exit

(config)#

enable

Name

enable - enables RIP on a router

Syntax

enable

no enable

flash-update-time

Routing Information Protocol (RIP) Page 285

Mode

RIP Router Configuration

Parameters

none

Description

The enable command enables the state RIP. The negative form of this command, no enable, disables

RIP on the router.

Default

If enable is not specified, it is the same as if the user had specified the following:

(config-router-rip)# enable

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables RIP on the router.

(config)# router rip

(config-router-rip)# no enable

(config-router-rip)# exit

(config)#

flash-update-time

Name

flash-update-time - sets the number of seconds between flash updates

Syntax

flash-update-time time-seconds

no flash-update-time time-seconds?

Mode

RIP Router Configuration

Parameters

time-seconds - an integer between 0 and 5, specifying a number of seconds

Description

The flash-update-time command configures the Flash Update time. By default. The flash-update-timer

is set to a random value with a range of (0, 5) inclusive. The negative form of this command, no

flash-update-time, removes the configured time-seconds value and returns this to a random number

between 0 and 5. Note: Specifying a value for time-seconds in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

The default Flash Update time value is a random number between 0 and 5.

ignore-host-routes

Routing Information Protocol (RIP) Page 286

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the flash-update-timer to be 3 seconds.

(config)# router rip

(config-router-rip)# flash-update-time 3

(config-router-rip)# exit

(config)#

ignore-host-routes

Name

ignore-host-routes - configures Advanced Routing Suite to reject host routes learned in RIP response

messages

Syntax

ignore-host-routes

no ignore-host-routes

Mode

RIP Router Configuration

Parameters

none

Description

The ignore-host-routes command causes Advanced Routing Suite to reject host routes (with a

netmask of 255.255.255.255) learned in RIP response messages. The negative form of this command, no ignore-host-routes, returns to the default setting of accepting host routes learned in RIP response messages.

Default

If ignore-host-routes is not specified, it is the same as if the user had specified the following:

(config-router-rip)# no ignore-host-routes

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the router to not recognize host routes.

(config)# router rip

(config-router-rip)# ignore-host-routes

(config-router-rip)# exit

(config)#

ignore-must-be-zero

Routing Information Protocol (RIP) Page 287

ignore-must-be-zero

Name

ignore-must-be-zero - configures the handling of zero-filled reserved fields in RIP 1

Syntax

ignore-must-be-zero

no ignore-must-be-zero

Mode

RIP Router Configuration

Parameters

none

Description

The RIP version 1 specification mandates that certain fields in RIP routing updates are reserved and should be filled with zeros. It also mandates that version 1 packets, where the reserved fields are not filled with all zeros, should be discarded. However, some implementations of RIP do not follow the specification and carry

non-zero information in these fields. The ignore-must-be-zero command allows RIP to interoperate

with those implementations.

The user should be certain that the non-compliant router is intentionally generating malformed packets (rather than malfunctioning) before enabling interoperability. Otherwise, correct routing could be compromised.

The negative form of this command, no ignore-must-be-zero, returns this command to the default of

checking zero-filled reserved fields for RIP version 1.

Default

If ignore-must-be-zero is not specified, it is the same as if the user had specified the following:

(config-router-rip)# no ignore-must-be-zero

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the RIP router to ignore messages whose reserved fields are not zeroed.

(config)# router rip

(config-router-rip)# ignore-must-be-zero

(config-router-rip)# exit

(config)#

network

Name

network - configures a network on which to run RIP

Syntax

network ipv4_address [ mask ]? {1,n}

preference

Routing Information Protocol (RIP) Page 288

no network ipv4_address [ mask ]?

Mode

RIP Router Configuration

Parameters

ipv4_address - a valid IPv4 address specified in dotted-quad notation

mask - specify the mask (wildcard bits) of the network IP address. Specifying this value is optional.

{1,n} - The network command can be specified multiple times in RIP Router Configuration mode.

Description

The network command specifies a network on which to run RIP. Use the command multiple times to build

a list of networks on which RIP is to run. If the optional mask is not specified, RIP will be enabled on all interfaces that match the natural mask of the network IP address, and that natural mask will display when

you issue a show running command. If the mask is supplied, then RIP will run on interfaces that match

both the network address and the mask.

Use the negative form of this command, no network, to stop running RIP on a network. Note: The

complete configuration must be provided in the negative command. For example, if you configured a network address and specified a mask, both values must appear in the negative command.

Default

RIP networks are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures RIP to run on interface 192.168.121.1 and the interface associated with network 192.168.11.0.

(config)# router rip

(config-router-rip)# network 192.168.121.1

(config-router-rip)# exit

(config)#

preference

Name

preference - specifies how active routes that are learned from RIP will be selected, compared to routes

learned from other protocols

Syntax

preference pref

no preference pref?

Mode

RIP Router Configuration

Parameters

pref - an integer from 0 (directly connected) to 255, inclusive

query-authentication

Routing Information Protocol (RIP) Page 289

Description

Routers can learn multiple routes to the same destination. Each routing protocol handles this internally, so, for example, if RIP learns two different routes to the same destination, it will select the route with the lower metric. However, a router can learn two routes to the same destination from different routing protocols, and it must find a way to choose between them. Advanced Routing Suite uses a preference number to make this decision, choosing the route with the lower preference. Normally, RIP routes are preferred to routes from external routing protocols (for example, BGP or OSPF ASE) and to those that are generated or aggregated. RIP routes are less preferable than those learned from other intra-domain routing protocols and those that

are statically configured. The preference command is used to change this ordering.

The negative form of this command, no preference, removes the configured pref value and returns this to

its default value of 100. Note: Specifying a value for pref in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If preference is not specified, it is the same as if the user had specified the following:

(config-router-rip)# preference 100

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a preference of 150 for RIP routes.

(config)# router rip

(config-router-rip)# preference 150

(config-router-rip)# exit

(config)#

query-authentication

Name

query-authentication - configures the authentication used by the ripquery utility

Syntax

query-authentication [ [simple key] | [md5 id_number md5_key (start-generate date_time || stop-generate date_time || start-accept date_time || stop-accept date_time)?] {0,4} ]

no query-authentication

Mode

RIP Router Configuration

Parameters

simple key - specifies simple (clear password) authentication. The value for key is specified by one to

eight decimal digits (with a value between 0 and 255) separated by periods, a one- to eight-byte hexadecimal string preceded by 0x, or a one- to eight-character string.

md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time)

|| (start-accept date_time) || (stop-accept date_time)] - specifies the authentication

used for specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is a one- to sixteen-character string. The start and

redistribute

Routing Information Protocol (RIP) Page 290

stop values must be in the format: YYYY-MM-DD.HH.MM. Each start and stop value is optional, and order is not important when specifying multiple commands.

{0,4} - up to 4 MD5 key values can be configured, provided each has a unique md5_key value.

Description

The ripquery utility was created for debugging RIP routers. This tool sends a RIP POLL packet, which is an

extension undocumented in the RFC. The query-authentication command is used to check the

incoming POLL packets. If the authentication matches, then RIP will reply with its full routing table. (It will not run split-horizon or poison reverse before replying.) If the authentication does not match, then the request will be discarded.

Although query-authentication uses the standard key format for passwords, the generate portions of

the key are irrelevant because the key is used only to check incoming requests. Outing packets use whatever authentication is set up on the interface over which the POLL packet was received.

Simple and md5 keys are mutually exclusive. Multiple md5 key values can be configured for an md5 authentication provided each key has a unique md5_key value.

Default

Query authentication is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a simple key password for Query Authentication.

(config)# router rip

(config-router-rip)# query-authentication simple abc

(config-router-rip)# exit

(config)#

Example 2

The following example configures md5 authentication with two key chains.

(config)# router rip

( config-router-rip)# query-authentication md5 1 abc start-accept 2003-12-01.10.20 stop-accept 2003-12-11.10.20 start-generate 2003-12-01.10.20 stop-generate 2003-12-11.10.20

(config-router-rip)# query-authentication md5 2 abc start-accept 2003-12-11.10.20 stop-accept 2003-12-21.10.20 start-generate 2003-12-11.10.20 stop-generate 2003-12-21.10.20

(config-router-rip)# exit

(config)#

redistribute

Name

redistribute - specifies routes to export to the current protocol

redistribute

Routing Information Protocol (RIP) Page 291

Syntax

redistribute protocol [route-map name]? {0,9}

no redistribute protocol [route-map name]?

Mode

RIP Router Configuration

Parameters

protocol - the protocol name whose routes you want to redistribute to the current protocol being configured.

Valid protocols are aggregate, bgp, direct, isis, kernel, ospf, ospf-ase, rip, and static.

route-map name - the name of a route map to apply to these routes. Specifying this is optional.

{0,9} - although this command can be given multiple times, it can only be given once for each of the nine

configurable protocols. In other words, if a redistribute command is given for a protocol and route map,

and then given again for the same protocol with a different route map, the second configuration overrides the first.

Description

Use the redistribute command to specify routes to export into the current protocol (BGP, OSPF-ASE,

RIP, or VRE). This command causes routes from the specified protocol to be considered for redistribution into the current protocol. Additionally, if a route map is specified, then routes from the specified protocol that match the named route map will be considered for redistribution into the current protocol. If the referenced route map has not yet been configured, then an empty route map is created with the specified name.

Note: Configuring this away from its default removes the implicitly configured default. You will have to go

back and specify to redistribute RIP and/or direct routes after the first redistribute configuration in order

to export those routes.

Default

The default is to export direct routes and RIP routes. Note that this is an implicit default that is wiped away with the first redistribute configuration.

Example

Example 1

In the following example RIP is configured to redistribute all BGP routes.

(config)# router rip

(config-router-rip)# redistribute bgp

(config-router-rip)# exit

(config)#

Example 2

The following example configures a community set, "set1", that permits AS:num 101:102. It then configures an extended community set "ext-set1", that permits Route Target AS:num 201:202.

(config)# ip community-set set1 permit 101:102

(config)# ip extcommunity-set ext-set1 permit rt 201:202

The two are then added to a community list, called "commlist1".

(config)# ip community-list commlist1 permit set1

(config)# ip community-list commlist1 permit ext-set1

The community list is then applied to a route map called "match-commlist1". If the route map matches BGP Community list "commlist1", then the metric for routes will be set to 20.

(config)# route-map match-commlist1

send-updates

Routing Information Protocol (RIP) Page 292

(config-route-map)# match community commlist1

(config-route-map)# set metric 20

(config-route-map)# exit

(config)#

Finally, the route map ("match-commlist1") is applied to BGP routes and exported into RIP.

(config)# router rip

(config-router-rip)# redistribute bgp route-map match-commlist1

(config-router-rip)# exit

(config)#

Example 3

In the following example, route map "abc" is configured with the following match criteria:

If a route matches interface "fxp1" and a pre-configured BGP Community labeled "bgpcomm1", then communities specified in community "com-set-1" will be added to the route, communities specified in community labeled "com-set-2" will be deleted from the route, and the metric of the route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match community-set bgpcomm1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

This route map is then applied to static routes and exported into RIP.

(config)# router rip

(config-router-rip)# redistribute static route-map abc

(config-router-rip)# exit

See Also

"distribute-list" ("distribute-list" on page 281)

send-updates

Name

send-updates - specifies the conditions under which RIP will be an active or a passive participant

Syntax

send-updates [on | off | multiple-interfaces]?

no send-updates

Mode

RIP Router Configuration

Parameters

on - configures updates to be sent even if only one interface is present

send-updates

Routing Information Protocol (RIP) Page 293

off - updates will not be sent regardless of the number of interfaces present

multiple-interfaces - optionally specify that, if multiple interfaces (either physical or logical) have

addresses on the same subnet, then RIP will send updates only on the first one for which RIP is configured to do so, regardless of configuration

Description

RIP is most often run on a multi-homed box to cause the machine to act as a router in small LANs; however, it is also run on single-homed machines, often to learn the default route or routes to other networks in the domain. RIP will try to guess whether it should act as a router (for example, whether it should act as an active participant in routing) by examining the number of interfaces available to it.

The send-updates command can be used to override this default behavior. Specifically, if send-updates

is specified without the multiple-interfaces or off options, then RIP updates will be sent even if only

one interface is present. This is the same behavior as the send-updates on command.

If the send-updates command is specified with the multiple-interfaces option, and if multiple

interfaces have addresses on the same subnet, then RIP will send updates only on the first for which RIP is

configured to do so, regardless of the configuration. Finally, if no send-updates is specified, or if

send-updates off is specified, then RIP updates will not be sent, regardless of the number of interfaces

present.

The no send-updates command is most often used to turn off active participation in a RIP cloud. This can

be used, for example, on a multi-homed machine running different protocols on different interfaces where it is desired not to send the other attached networks or learned routes into the RIP cloud. The same functionality can be achieved through policy rules. But for a simple network, that degree of configuration complexity is not necessary.

Note: All values of send-updates apply only to broadcasting (or multicasting, in the case of RIP version 2)

of RIP packets.

Default

If send-updates is not specified, it is the same as if the user had specified the following:

(config-router-rip)# send-updates multiple-interfaces

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures RIP to send updates, even if only one interface is present.

(config)# router rip

(config-router-rip)# send-updates

(config-router-rip)# exit

(config)#

Example 2

The following example configures RIP to not send any updates to an interface.

(config)# router rip

(config-router-rip)# no send-updates

(config-router-rip)# exit

(config)#

source-gateways

Routing Information Protocol (RIP) Page 294

source-gateways

Name

source-gateways - specifies the routers to which RIP will unicast update messages

Syntax

source-gateways ipv4_address {n}

no source-gateways ipv4_address

Mode

RIP Router Configuration

Parameters

ipv4_address - a valid IPv4 address in dotted-quad notation

{n} - This command can be specified multiple times to configure a complete list of IP addresses to which

the configured router will unicast RIP updates.

Description

The source-gateways command allows you to configure a complete list of IP addresses to which the

configured router will unicast RIP updates. Note: RIP must be configured on an interface that shares a subnet with each gateway address.

If any source gateways are specified, then no RIP packets will be broadcast or multicast. They will only be unicast to the list of source gateways. If no source gateways are specified, Advanced Routing Suite will not unicast updates.

Use the negative form of this command, no source-gateways, with a specific IPv4 address to remove

one source gateway address from the configured list. Use the negative form with no specified address to delete the entire list of source gateways.

Default

By default, RIP will either broadcast or multicast its updates. Thus, if source-gateways is not specified, it

is the same as if the user had specified the following:

(config-router-rip)# no source-gateways

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

In the following example, a list of three source-gateways is configured. Advanced Routing Suite will unicast updates to the source gateways 192,168.10.1, 101.168.11.1, and 192.168.12.1.

(config)# router rip

(config-router-rip)# source-gateways 192.168.10.1

(config-router-rip)# source-gateways 192.168.11.1

(config-router-rip)# source-gateways 192.168.12.1

(config-router-rip)# exit

(config)#

Example 2

In the following example, the source-gateway 192.168.11.1 from Example 1 is deleted.

split-horizon

Routing Information Protocol (RIP) Page 295

(config)# router rip

(config-router-rip)# no source-gateways 192.168.11.1

(config-router-rip)# exit

(config)#

Example 3

In the following example, the rest of the entire source-gateways list from Example 1 is deleted. As a result, RIP will send updates by broadcast or multicast.

(config)# router rip

(config-router-rip)# no source-gateways

(config-router-rip)# exit

(config)#

split-horizon

Name

split-horizon - configures the split horizon feature for RIP

Syntax

split-horizon [ on | off | poison-reverse ]

no split-horizon

Mode

RIP Router Configuration Mode

Parameters

on - RIP will not announce a route back to the interface from which the route is learned

off - RIP will announce a route to all possible interfaces, including the interface from which the route was

learned

poison-reverse - RIP will announce a route to all possible interfaces, including the interface from which

the route was learned, but with the infinity metric

Description

The split-horizon command configures the way horizon split is performed. This command has three

forms. If on is specified, then the simple split-horizon mechanism is enabled. This means that RIP will not

announce a route back to the interface from which the route was learned. If off is specified, then the split

horizon mechanism is disabled. This means that RIP will announce a route to all possible interfaces,

including the interface from which the route was learned. Finally, if poison-reverse is specified, then split

horizon with poisoned reverse is enabled. This means that RIP will announce a route to all possible interfaces, including the one from which the route was learned, but with the infinity metric.

The negative form of this command, no split-horizon, removes the configured split horizon type and

returns this to its default type .

Default

If split-horizon is not specified, it is the same as if the user had specified the following:

(config-router-rip)# split-horizon on

term-updates

Routing Information Protocol (RIP) Page 296

Examples

Example 1

In the following example, RIP is configured without split horizon.

(config)# router rip

(config-router-rip)# split-horizon off

(config-router-rip)# exit

(config)#

Example 2

In the following example, RIP is configured with split horizon with poisoned reverse.

(config)# router rip

(config-router-rip)# split-horizon poison-reverse

(config-router-rip)# exit

(config)#

Example 3 In the following example, RIP is configured to return to the default behavior of split horizon. Split horizon will be the effect.

(config)# router rip

(config-router-rip)# no split-horizon

(config-router-rip)# exit

(config)#

term-updates

Name

term-updates - sets the number of updates sent by RIP during termination

Syntax

term-updates number

no term-updates number?

Mode

RIP Router Configuration

Parameters

number - an integer between 1 and 255, inclusive

Description

The term-updates command configures the number of updates sent by RIP during termination. The

negative form of this command, no term-updates, removes the configured number value and returns this

to its default value of 4. Note: Specifying a value for number in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

timers basic

Routing Information Protocol (RIP) Page 297

Default

If term-updates is not specified, it is the same as if the user had specified the following:

(config-router-rip)# term-updates 4

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a term update number of 6.

(config)# router rip

(config-router-rip)# term-updates 6

(config-router-rip)# exit

(config)#

timers basic

Name

timers basic - sets the Update Interval, Expiration Time, and Holddown Time for routes received or sent

via RIP

Syntax

timers basic update-seconds expiration-seconds holddown-seconds

no timers basic [update-seconds expiration-seconds holddown-seconds]?

Mode

RIP Router Configuration

Parameters

update-seconds - the update interval in seconds, specified as an integer from 5 to 4,294,967,295 inclusive

expiration-seconds - the route expiration time in seconds, specified as an integer from5 to 4,294,967,295

inclusive

holddown-seconds - configures the holddown time in seconds, specified as an integer from 5 to

4,294,967,295 inclusive

Description

The timers basic command sets the Update Interval, the Expiration Time, and the Holddown Time in

seconds for routes received and/or sent via RIP. The negative form of this command, no timers basic,

returns this value to its default. Specifying values for update-seconds, expiration-seconds, and

holddown-seconds in the no form has no effect on the configuration. Thus, they are displayed above as

optional.

Note: When configuring timers basic, you must specify an update-seconds value, an expiration-seconds

value, and a holddown-seconds value, in that order, even if you want one or two of these to remain the default value.

Default

If timers basic is not configured, it is the same as if the user had specified the following:

(config-router-rip)# timers basic 30 180 120

trace file

Routing Information Protocol (RIP) Page 298

Command History

NGC 2.2 - This command was introduced.

NGC 2.3 - The Holddown Timer value was added to this command. In addition, each of the previous value ranges changed to 5 to 4,294,967,295 inclusive.

Examples

Example 1

The following example configures the Update Interval to be 25 seconds, the Expiration Time to be 150 seconds, and the Holddown Timer to be 300 seconds.

(config)# router rip

(config-router-rip)# timers basic 25 150 300

(config-router-rip)# exit

(config)#

Example 2

The following example configures the Expiration Time to be 200 seconds. The Update Interval will have the default value of 30 seconds. The Holddown Timer will also have its default value. Note that you must specify the Update Interval and Holddown Timer values even though you are configuring the default.

(config)# router rip

(config-router-rip)# timers basic 30 200 120

(config-router-rip)# exit

(config)#

Example 3

The following example removes any configured timer values and returns the timers basic command to its

default values.

(config)# router rip

(config-router-rip)# no timers basic

(config-router-rip)# exit

(config)#

trace file

Name

trace file - specifies the file to receive tracing information, the size of the file, whether to overwrite

existing files, and the maximum number of files allowed

Syntax

trace file file_name [no-timestamp || overwrite]?

no trace file file_name [no-timestamp || overwrite]?

Mode

RIP Router Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

trace flag

Routing Information Protocol (RIP) Page 299

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For RIP, the trace file command in RIP Router Configuration

Mode specifies a file for tracing of all RIP events. The negative form of this command disables this tracing.

The specific events that are traced are controlled by the trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands.

Default

RIP tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, RIP tracing is written to the file "rip.log". No timestamp will display at the beginning of the trace lines.

(config)# router rip

(config-router-rip)# trace file rip.log no-timestamp

trace flag

Name

trace flag - specifies RIP-specific tracing options as well as options that are common across all

protocols

Syntax

trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packets | request | response | other ] [ send | receive | send-receive ]? [detail?] )

no trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packets | request | response | other ] [ send | receive | send-receive ]? [detail?] )

Mode

RIP Router Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

trusted-gateways

Routing Information Protocol (RIP) Page 300

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

IP-specific flags:

[ packets | request | response | other ] - These RIP-specific flags can be associated with the

send, receive, or send-receive action items. These flags are defined as follows:

packets - trace all RIP packet types

request - trace RIP information request packets, which include request, poll, and poll entry packets

response - trace RIP response packets (for example, those that actually contain routing updates)

other - trace any other type of RIP packet

[send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the trace flag command to specify tracing flags for RIP tracing. Each flag must reside on its own

configuration line. For example, you cannot specify to trace both task and policy packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received request and response messages are traced in detail. This tracing information will be written to the file rip.log.

(config)# router rip

(config-router-rip)# trace file rip.log

(config-router-rip)# trace flag request send-receive detail

(config-router-rip)# trace flag response send-receive detail

(config-router-rip)# exit

(config)#

trusted-gateways

Name

trusted-gateways - configures the routers from which RIP will accept routes

Syntax

trusted-gateways ipv4-address {n}

trusted-gateways

Routing Information Protocol (RIP) Page 301

no trusted-gateways ipv4-address?

Mode

RIP Router Configuration

Parameters

ipv4-address - a valid IPv4 address in dotted-quad notation

{n} - This command can be repeated an unlimited number of times to created an unlimited number of

trusted gateways.

Description

The trusted-gateways command configures routers from which RIP will accept routes. Update

messages from routes not specified in this command will be discarded. This allows for additional security beyond that provided by "ip rip authentication" ("ip rip authentication" on page 302). Specifically, it provides a complete list of IP addresses from which the configured router will accept RIP updates. Only those RIP packets originating from the listed hosts will be accepted.

Use the negative form of this command, no trusted-gateways, with an IPv4 address to remove a single

address from the list of trusted gateways. To delete the entire list, use the negative form of the command with no IPv4 address.

Default

All routers are trusted by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures RIP to accept updates sent from routes with only host addresses of 2 on the 192.168.10, .12, and .13 networks.

(config)# router rip

(config-router-rip)# trusted-gateways 192.168.10.2

(config-router-rip)# trusted-gateways 192.168.11.2

(config-router-rip)# trusted-gateways 192.168.12.2

(config-router-rip)# exit

(config)#

Example 2

In the following example, the trusted-gateway 192.168.11.1 from Example 1 is deleted.

(config)# router rip

(config-router-rip)# no trusted-gateways 192.168.11.1

(config-router-rip)# exit

(config)

Example 3

In the following example, the rest of the entire trusted-gateways list from Example 1 is deleted. As a result, RIP will trust all routers.

(config)# router rip

(config-router-rip)# no trusted-gateways

ip rip authentication

Routing Information Protocol (RIP) Page 302

(config-router-rip)# exit

(config)#

ip rip authentication

Name

ip rip authentication - specifies the type of authentication and key values

Syntax

ip rip authentication [ [simple key] | [md5 id_number md5_key (start-generate date_time || stop-generate date_time || start-accept date_time || stop-accept date_time)?] {0,4} ]

no ip rip authentication

Mode

Interface Configuration

Parameters

simple key - specifies simple (clear password) authentication. The value for key is specified by one to

eight decimal digits (with a value between 0 and 255) separated by periods, a one- to eight-byte hexadecimal string preceded by 0x, or a one- to eight-character string.

md5 id_number md5_key [(start-generate date_time) || (stop-generate date_time)

|| (start-accept date_time) || (stop-accept date_time)] - specifies the authentication

used for specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is a one- to sixteen-character string. The start and stop values must be in the format: YYYY-MM-DD.HH.MM. Each start and stop value is optional, and order is not important when specifying multiple commands.

{0,4} - up to 4 MD5 key values can be configured, provided each has a unique md5_key value.

Description

The ip rip authentication command is used both to verify and to generate the authentication field in

the RIP header for all packets sent and received on the specified interface. This applies only to version 2 packets and RIPv1-compatible RIPv2 packets, because RIPv1 does not support authentication. One exception to the above is the case of query packets. In the case of querying a router through an interface that is speaking RIPv1, the query packet will still be authenticated, but no authentication will be used on the outgoing packet.

If a packet is received with authentication that does not match, then it is ignored.

On a trusted network, simple authentication can be used to create two logical networks because sets of routers with shared passwords will talk to each other, but not communicate with those using a different password. On an untrusted network, however, this technique should not be used because simple passwords are sent in clear text. MD5 should be used instead. However, even MD5 does not encrypt the entire packet, only the authentication field of the header.

Specifying an authentication without explicitly configure RIP to version 2 will cause a parse error. For somewhat more serious authentication, use trusted gateways or a combination of trusted gateways and authentication.

Default

The default is for no authentication to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

ip rip enable

Routing Information Protocol (RIP) Page 303

Examples

Example 1

The following example configures a simple key authentication for interface fxp1.

(config)# interface fxp1

(config-if)# ip rip authentication simple abc

(config-if)# exit

(config)#

Example 2

The following example configures md5 authentication with two keys on interface fxp0.

(config)# interface fxp0

(config-if)# ip rip authentication md5 1 abc start-accept 2003-12-01.10.20 start-generate 2003-12-01.10.20

(config-if)# ip rip authentication md5 2 abc start-accept 2003-12-11.10.20 stop-accept 2003-12-21.10.20

(config-if)# exit

(config)#

ip rip enable

Name

ip rip enable - enables RIP on an interface

Syntax

ip rip enable

no ip rip enable

Parameters

none

Description

The ip rip enable command explicitly enables RIP on an interface. The no ip rip enable command

explicitly disables RIP on an interface.

Default

If ip rip enable is not specified, it is the same as if the user had specified the following:

(config-if)# no ip rip enable

Command History

NGC 2.2 - This command was introduced

Examples

The following example disables RIP on interface fxp2.

(config)# interface fxp2

(config-if)# no ip rip enable

ip rip metric-in

Routing Information Protocol (RIP) Page 304

(config-if)# exit

(config)#

ip rip metric-in

Name

ip rip metric-in - sets an additional metric on incoming RIP routers for an interface

Syntax

ip rip metric-in value

no ip rip metric-in value?

Mode

Interface Configuration

Parameters

value - an integer in the range of 0 to 16, inclusive

Description

The ip rip metric-in command sets an additional metric on incoming RIP routes for an interface.

It is often the case that a router should prefer routes received on one set of interfaces over those received on another. For example, given two point-to-point links, one can be more expensive than the other and

should, therefore, be less preferred. The ip rip metric-in command is used for exactly this purpose: to

make routes learned from certain interfaces less preferable.

ip rip metric-in is the default manner by which RIP increments hop count. That is to say, RIP works by

adding a hop every time a route is received and before it is sent back out to other interfaces. This implementation adds the hop when the route is received (for example, before decisions regarding whether the route should be used are made). By default, a metric of 1 plus the kernel interface metric is added as the hop count. Normally, this interface metric is zero, but some operating systems allow it to be specified on

interface configuration. If ip rip metric-in is explicitly given, it is added as an absolute value (for

example, without the interface metric).

The negative form of this command, no ip rip metric-in, returns this to its default value. Note:

Specifying a value in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip rip metric-in is not specified, it is the same as if the user had specified the following:

(config-if)# ip rip metric-in 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a router to add a metric of 2 to the incoming RIP routes on interface fxp0.

(config)# interface fxp0

(config-if)# ip rip metric-in 2

(config-if)# exit

(config)#

ip rip metric-out

Routing Information Protocol (RIP) Page 305

ip rip metric-out

Name

ip rip metric-out - sets an additional metric on outing RIP routes for an interface

Syntax

ip rip metric-out value

no ip rip metric-out value?

Mode

Interface Configuration

Parameters

value - an integer between 0 and 16, inclusive

Description

The ip rip metric-out command configures an addition metric on outgoing RIP routes for an interface.

Normally, this RIP implementation adds to the hop count only on incoming routes. There are times, however, when the user wants to cause other routers not to prefer routes from a given origin. For example, if

the router is a backup router, it might be desirable for its routes to always be less preferred. ip rip

metric-out accomplishes this by adding to the RIP metric on top of any metric specified by ip rip

metric-in before RIP updates are sent out the specified interface.

Use the negative form of this command, no ip rip metric-out, to remove a configured value and return

this to its default value of 0. Note: Specifying a value in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If ip rip metric-out is not specified, it is the same as if the user had specified the following:

(config-if) ip rip metric-out 0

Example

The following example configures a router to add a cost of 2 to outgoing RIP routes for interface fxp0.

(config)# interface fxp0

(config-if)# ip rip metric-out 2

(config-if)# exit

(config)#

ip rip no-receive

Name

ip rip no-receive - specifies whether RIP will listen to or discard RIP updates

Syntax

ip rip no-receive

no ip rip no-receive

ip rip no-send

Routing Information Protocol (RIP) Page 306

Mode

Interface Configuration

Parameters

none

Description

The ip rip no-receive command specifies whether RIP will listen to RIP updates received on a given

interface. Although it would almost certainly be a mis-configuration, it is important to note that RIP can send RIP updates on a superset of those interfaces on which it receives updates. This can be a valid configuration if, for example, the user receives RIP updates from an ISP, then redistributes those onto the LAN, and does not want to send the LAN topology back to the ISP.

Default

By default, RIP listens to updates received on a given interface. Therefore, if ip rip no-receive is not

specified, it is the same as if the user had specified the following:

(config-if)# no ip rip no-receive

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures no-receive on interface fxp0. As a result, updates received on interface fxp0 will be discarded.

(config)# interface fxp0

(config-if)# ip rip no-receive

(config-if)# exit

(config)#

ip rip no-send

Name

ip rip no-send - specifies whether RIP will send RIP updates

Syntax

ip rip no-send

no ip rip no-send

Mode

Interface Configuration

Parameters

none

Description

RIP, by default, sends updates on interfaces on which RIP is running. The ip rip no-send command

specifies that RIP will not send updates.

ip rip secondary-authentication

Routing Information Protocol (RIP) Page 307

Default

If ip rip no-send is not specified, it is the same as if the user had specified the following:

(config-if)# no ip rip no-send

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the no-send option on interface fxp1. As a result, no updates will be send over that interface.

(config)# interface fxp1

(config-if)# ip rip no-send

(config-if)# exit

(config)#

ip rip secondary-authentication

Name

ip rip secondary-authentication - sets the authentication used on an interface if the primary

authentication fails

Syntax

ip rip secondary-authentication [ [simple key] | [md5 id_number md5_key (start-generate date_time || stop-generate date_time || start-accept date_time || stop-accept date_time)?] {0,4} ]

no ip rip secondary-authentication

Mode

Interface Configuration

Parameters

simple key - specifies simple (clear password) authentication. The value for key is specified by one to

eight decimal digits (with a value between 0 and 255) separated by periods, a one- to eight-byte hexadecimal string preceded by 0x, or a one- to eight-character string.

md5 id_number md5_key (start-generate date_time || stop-generate date_time ||

start-accept date_time || stop-accept date_time)? - specifies the authentication used for

specifying md5 cryptographic authentication. The value for id_number is an integer with a value between 1 and 255, inclusive. The value for md5_key is specified by one to eight decimal digits (with a value between 0 and 255) separated by periods, a one- to eight-byte hexadecimal string preceded by 0x, or a one- to eight-character string. The start and stop values must be in the format: YYYY/MM/DD HH:MM.

{0,4} - up to 4 md5 key values can be configured, provided each has a unique md5_key value.

Description

The ip rip secondary-authentication is identical in function to the primary authentication configured

using the ip rip authentication command but is only used if the primary authentication fails. This type

of authentication can be used while a network is in transition to verify that old passwords are still accepted.

Use the negative form of this command, no ip rip secondary-authentication, to remove the

configured authentication.

ip rip version

Routing Information Protocol (RIP) Page 308

Default

The default is for no authentication to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a simple key authentication for interface fxp0.

(config)# interface fxp0

(config-if)# ip rip secondary-authentication simple abc

(config-if)# exit

(config)#

Example 2

The following example configures md5 authentication with two keys on interface fxp0.

(config)# interface fxp0

(config-if)# ip rip secondary-authentication md5 1 abc start-accept 2003/12/01 10:20 start-generate 2003/12/01 10:20

(config-if)# ip rip secondary-authentication md5 2 abc start-accept 2003/12/11 10:20 stop-accept 2003/12/21 10:20

(config-if)# exit

(config)#

ip rip version

Name

ip rip version - specifies the version of RIP to be run on an interface

Syntax

ip rip version [ 1 | 2 [ broadcast | multicast ]? ]

no ip rip version

Mode

Interface Configuration

Parameters

1 - specify to run RIP version 1 on the interface

2 [ broadcast | multicast ] - specify to run RIP version 2 on the interface. Also, optionally specify

whether updates will be sent to a multicast group or will be broadcast to the network

Description

The ip rip version command specifies the version of RIP to be run. This command is used to override

the default version of RIP that will be run on a given interface. Normally, RIPv1 will be run on all interfaces. If version 2 is specified, then the default behavior depends on the capabilities of the interface. If the interface is multicast capable, then RIP updates will be multicast to RIP2-ROUTERS.MCAST.NET (the reserved multicast address, 224.0.0.9). If the interface is not multicast capable, then RIP version 1 compatible version 2 will be broadcast.

show ip rip database

Routing Information Protocol (RIP) Page 309

The optional broadcast and multicast parameters are effective only if RIP version 2 is configured.

Specifying broadcast or multicast allows the above default behavior to be overridden. This is normally

used to specify that only version-1-compatible packets should be sent for interoperability purposes, even though a given interface is multicast capable. An exception is the case in which version 2 multicast is specified on an interface that is not multicast capable (for example, a point-to-point link). In this case, if a source-gateway is also specified, then the full RIPv2 packets will be directly unicast to the source gateway on the specified interface.

Default

If ip rip version is not specified, it is the same as if the user had specified the following:

(config-if)# ip rip version 1

If version 2 is being configured on multicast-capable interfaces without specifying multicast or

broadcast, it is the same as if the user had specified the following:

(config-if)# ip rip version2 multicast

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures version 2 broadcast on interface fxp0.

(config)# interface fxp0

(config-if)# ip rip version 2 broadcast

(config-if)# exit

(config)#

Example 2

In the following example, the version setting in Example 1 is set back to using the default behavior for interface fxp0. Version 1 packets will then be broadcast to the network.

(config)# interface fxp0

(config-if)# no ip rip version

(config-if)# exit

(config)#

Example 3

The following example configures version 2 on multicast-capable interface fxp1. Updates will be sent out to multicast group 224.0.0.9.

(config)# interface fxp1

(config-if)# ip rip version 2

(config-if)# exit

(config)#

show ip rip database

Name

show ip rip database - displays information about a specific route or all routes in the Routing

Information Base

show ip rip database

Routing Information Protocol (RIP) Page 310

Syntax

show ip rip database [(ipv4-address mask) | (tag value)]?

Mode

User Execution

Parameters

ipv4-address mask - optionally enter a specific IPv4 address and subnet mask argument about which routing information should be displayed

tag value - optionally specify a tag and value used to mark a specific route. The tag value can be an

integer from 0 to 4,294,967,295, inclusive.

Description

The show ip rip database query displays information about routes in the Routing Information Base. This

query has three forms. If the query is issued without arguments, then information about all RIP routes is returned. Alternatively, the query can be issued with a specific IPv4 address and mask. In this case, the reply will contain information pertaining only to the referenced address. Finally, a query can be submitted with a tag value. In this case, all RIP routes that match the tag will be displayed.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example displays all rip routes.

> show ip rip database

192.168.11.0/24 directly connected, fxp0 192.168.13.0/24 [1] via 192.168.14.2, 00:00:25, fxp0 [2] via 192.168.15.2, 00:00:20, fxp1 182.168.13.0/24 [1] via 182.168.14.2, 00:00:25, fxp3

Example 2

In the following example, a query is submitted for RIP route information for a specific network.

> show ip rip database 192.168.13.0 255.255.255.0

192.168.13.0/24 [1] via 192.168.14.2, 00:00:25, fxp0 [2] via 192.168.15.2, 00:00:20, fxp1

Example 3 In the following example, a query is submitted for information about RIP routes that match a given tag, 1000. The return shows one route that matches the tag.

> show ip rip database tag 1000

192.168.13.0/24 [1] via 192.168.14.2, 00:00:25, fxp3

Field Descriptions

The following table describes the fields that appear in the RIP Database Query (using fields in Example 1).

show ip rip database

Routing Information Protocol (RIP) Page 311

Table 18-1 RIP Database Query Fields

Field Description

192.168.11.0/24 Destination IPv4 address and mask length

directly connected Displays if the network is directly connected

[1] via 192.168.14.2 The first gateway

[2] via 192.168.15.2 The second gateway

00:00:25 Last heard time in hours:minutes:seconds

fxp0 The interface from which a nexthop can be reached

Page 312

Chapter 14

SNMP Multiplexing (SMUX)

In This Chapter

SNMP Multiplexing (SMUX) Overview 312

smux password 312

smux port 313

smux trace file 314

smux trace flag 314

SNMP Multiplexing (SMUX) Overview Support for the SMUX (RFC 1227) protocol is unique to Advanced Routing Suite due to its intended installation as a daemon running on a multi-user timeshare operating system. While this paradigm continues to evolve, an original intent of the SMUX protocol implement was to allow Advanced Routing Suite to inter-operate with another daemon handling the SNMP protocol and communicate with management stations. This allows Advanced Routing Suite to handle only a set of SNMP subtrees relating to the protocols implemented there.

Advanced Routing Suite supports SMUX as the only way to interact with the MIB modules. Only SNMP version 1 is supported, and all MIB variables are read-only.

Upon contacting the master agent, a string password and SNMP Object Identifier identity are passed for authentication purposes. If the authentication succeeds, Advanced Routing Suite will register the routing MIB subtrees and request that it be contacted when the master agent receives queries for these subtrees. When the master agent receives such a query from a management station, it will be passed to Advanced Routing Suite.

smux password

Name

smux password - specifies the clear text password to be used for authentication

Syntax

smux password string_value

no smux password string_value?

Mode

Global Configuration

Parameters

string_value - a string with a maximum of 255 characters for the SMUX opening password

Description

The SMUX protocol allows a clear text password to be used for authentication of the subagent. This

password is configured using the smux password command. The negative of this command, no smux

smux port

SNMP Multiplexing (SMUX) Page 313

password, removes the specified string_value and returns to the default of a blank password. Note:

Specifying a value for string_value in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Default

The default is a blank password with 0 length.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures "abc" as the clear text password for authentication of the subagent

(config)# smux password abc

smux port

Name

smux port - specifies the port on which to contact the master agent via TCP

Syntax

smux port port_value

no smux port port_value?

Mode

Global Configuration

Default

port_value - a port number on which to contact the master agent. This must be an integer from 0 to 65535,

inclusive.

Description

The master agent can be running on a different port than the well-known port of 199. This allows Advanced

Routing Suite to contact the agent on the specified port. The negative of this command, no smux port,

removes the specified port_value and returns this to the default port value of 199. Note: Specifying a value

for port_value in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If smux port is not specified, it is the same as if the user had specified the following:

(config)# smux port 199

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, the master agent is configured to run on port 2112.

(config)# smux port 2112

smux trace file

SNMP Multiplexing (SMUX) Page 314

smux trace file

Name

smux trace file - specifies the file to receive tracing information, the size of the file, whether to overwrite

existing files, and the maximum number of files allowed when tracing in SNMP Multiplexing

Syntax

smux trace file file_name [no-timestamp || overwrite]?

no smux trace file file_name [no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For SMUX, the smux trace file command specifies a file for tracing

of all SMUX events. The negative form of this command disables this tracing. The specific events that are

traced are controlled by the smux trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config)# smux trace file smux.log no-timestamp

Default

SMUX tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, SMUX tracing is written to the file "smux.log". No timestamp will display at the beginning of the trace lines.

(config)# smux trace file smux.log no-timestamp

smux trace flag

Name

smux trace flag - specifies SMUX-specific tracing options as well as options that are common across all

protocols

smux trace flag

SNMP Multiplexing (SMUX) Page 315

Syntax

smux trace flag ( [ route | normal | state | policy | task | timer | all | send | receive | packets ] )

no smux trace flag ( [ route | normal | state | policy | task | timer | all | send | receive | packets ] )

Mode

Global Configuration

Parameters

[ route | normal | state | policy | task | timer | all | send | receive | packets

] - These tracing flags are common to all protocols. They cannot be associated with a send, receive, or

detail action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

send - trace packets sent by the master agent

receive - trace packets received from the master agent

packets - trace every byte of traced packet

Description

Use the smux trace flag command to specify tracing flags for SMUX tracing. Each flag must reside on its

own configuration line. For example, you cannot specify to trace both packets and send in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, flags specify to trace packets and receive information. This tracing information will be written to the file smux.log.

(config)# smux trace file smux.log max-size 1024k

(config)# smux trace flag packets

(config)# smux trace flag receive

Page 316

Chapter 15

Distance Vector Multicast Routing Protocol (DVMRP)

In This Chapter

Distance Vector Multicast Routing Protocol (DVMRP) Overview 316

ip dvmrp 316

ip dvmrp distance 317

ip dvmrp default-metric 318

ip dvmrp disable 319

ip dvmrp metric-offset 319

ip dvmrp nodvmrpout 320

ip dvmrp noretransmit 321

ip dvmrp prune-lifetime 322

ip dvmrp trace file 323

ip dvmrp trace flag 324

ip dvmrp unicast-routing 325

show ip dvmrp interfaces 326

show ip dvmrp neighbors 327

show ip dvmrp route 328

tunnel mode dvmrp 330

Distance Vector Multicast Routing Protocol (DVMRP) Overview

DVMRP is the original IP multicast routing protocol. It was designed to run over both multicast capable LANs (like Ethernet) as well as through non-multicast capable routers. In the case of non-multicast capable routers, the IP multicast packets are "tunneled" through the routers as unicast packets. Because DVMRP replicates the packets, it has an effect on performance, but has provided an intermediate solution for IP multicast routing on the Internet while router vendors decide to support native IP multicast routing.

When configured, DVMRP defaults to enabling all interfaces that are multicast capable.

ip dvmrp

Name

ip dvmrp - enables the DVMRP protocol

Syntax

ip dvmrp

no ip dvmrp

ip dvmrp distance

Distance Vector Multicast Routing Protocol (DVMRP) Page 317

Mode

Interface Configuration

Parameters

none

Description

The ip dvmrp command enables the DVMRP protocol on the referenced interface. This command turns on

both DVMRP tree-building operations and DVMRP routing. The command turns off both DVMRP tree building and routing.

Default

By default, DVMRP is not enabled on an interface.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enables DVMRP on interfaces eth0 and eth1.

(config)# interface eth0

(config-if)# ip dvmrp

(config-if)# exit

(config)# interface eth1

(config-if)# ip dvmrp

(config-if)# exit

(config)#

ip dvmrp distance

Name

ip dvmrp distance - configures the value that Advanced Routing Suite uses for DVMRP routes in the

active route selection process

Syntax

ip dvmrp distance pref

no ip dvmrp distance pref?

Mode

Global Configuration

Parameters

pref - an integer between 0 and 255, inclusive

Description

The ip dvmrp distance command specifies how active routes that are learned from DVMRP will be

selected, compared to other protocols. When a route has been learned from more than one protocol, the active route will be selected from the protocol with the lowest distance. This value applies to all interfaces on which DVMRP is running.

ip dvmrp default-metric

Distance Vector Multicast Routing Protocol (DVMRP) Page 318

The negative form of this command, no ip dvmrp distance, removes the configured value and returns

this to its default value of 70. Note: Specifying a value for pref in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If ip dvmrp distance is not specified, it is the same as if the user had specified the following:

(config)# ip dvmrp distance 70

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the administrative distance for DVMRP to be 40.

(config)# ip dvmrp distance 40

ip dvmrp default-metric

Name

ip dvmrp default-metric - specifies the default value for the interface metric

Syntax

ip dvmrp default-metric value

no ip dvmrp default-metric value?

Mode

Global Configuration

Parameters

value - an integer ranging from 1 to 32, inclusive

Description

The ip dvmrp default-metric command specifies the default metric applied to all interfaces on which

DVMRP is running. This value can be overridden at the interface level. (See "ip dvmrp metric-offset" ("ip dvmrp metric-offset" on page 319).)

The negative form of this command, no ip dvmrp default-metric, removes the configured value and

returns this to its default value of 1. Note: Specifying a value for value in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If ip dvmrp default-metric is not specified, it is the same as if the user had specified the following:

(config)# ip dvmrp default-metric 1

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a default metric of 10.

(config)# ip dvmrp default-metric 10

ip dvmrp disable

Distance Vector Multicast Routing Protocol (DVMRP) Page 319

ip dvmrp disable

Name

ip dvmrp disable - disables DVMRP on an interface

Syntax

ip dvmrp disable

no ip dvmrp disable

Mode

Interface Configuration

Parameters

none

Description

The ip dvmrp disable command specifies that DVMRP messages received on the current interface must

be ignored. The negative form of this command, no ip dvmrp disable, re-enables DVMRP on an

interface.

Default

DVMRP runs on all interfaces by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example disables DVMRP on interface fxp1.

(config)# interface fxp1

(config-if)# ip dvmrp disable

(config-if)# exit

(config)#

ip dvmrp metric-offset

Name

ip dvmrp metric-offset - specifies the default value for the interface metric

Syntax

ip dvmrp metric-offset in metric

no ip dvmrp metric-offset in metric?

Mode

Interface Configuration

Parameters

in - specify that this metric applies to the incoming interface

ip dvmrp nodvmrpout

Distance Vector Multicast Routing Protocol (DVMRP) Page 320

metric - an integer value ranging from 1 to 32, inclusive

Description

The ip dvmrp metric-offset command sets the metric to add to all routes learned from neighbors

reached through this interface. The negative form of this command, no ip dvmrp metric-offset,

removes the configured value and re-sets this to its default value of 1. Note: Specifying a value for metric in

the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip dvmrp metric-offset is not specified, it is the same as if the user had specified the following:

(config-if)# ip dvmrp metric-offset in 1

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

In the following example, a metric of 5 is added to the route metric for each route learned from neighbors reached through interface eth0.

(config)# interface eth0

(config-if)# ip dvmrp metric-offset in 5

(config-if)# exit

(config)#

Example 2

In the following example, a metric of 8 is added to the route metric for each route learned from neighbors reached through interface eth1.

(config)# interface eth1

(config-if)# ip dvmrp metric-offset in 8

(config-if)# exit

(config)#

ip dvmrp nodvmrpout

Name

ip dvmrp nodvmrpout - tells DVMRP to only listen on an interface

Syntax

ip dvmrp nodvmrpout

no ip dvmrp nodvmrpout

Mode

Interface Configuration

Parameters

none

ip dvmrp noretransmit

Distance Vector Multicast Routing Protocol (DVMRP) Page 321

Description

The ip dvmrp nodvmrpout command disables DVMRP as a speaker on an interface, although it will

continue to listen and accept routes.

Default

By default, DVMRP acts as a speaker. Therefore, if ip dvmrp nodvmrpout is not specified, it is the same

as if the user had specified the following:

(config-if)# no ip dvmrp nodvmrpout

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes interface eth0 to listen and accept routes, but not to act as a speaker.

(config)# interface eth0

(config-if)# ip dvmrp nodvmrpout

(config-if)# exit

(config)#

ip dvmrp noretransmit

Name

ip dvmrp noretransmit - specifies to refrain from re-sending DVMRP prune packets

Syntax

ip dvmrp noretransmit

no ip dvmrp noretransmit

Mode

Interface Configuration

Parameters

none

Description

The ip dvmrp noretransmit command configures Advanced Routing Suite to not perform the

exponential backoff prune retransmission. After the transmission of the first prune, no additional prunes will be transmitted on reception of data until the prune lifetime has expired.

Default

The exponential backoff mechanism is performed by default. Therefore, if ip dvmrp noretransmit is not

specified, it is the same as if the user had specified the following:

(config-if)# no ip dvmrp noretransmit

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures interface eth1 to not perform the exponential prune backoff mechanism.

ip dvmrp prune-lifetime

Distance Vector Multicast Routing Protocol (DVMRP) Page 322

(config)# interface eth1

(config-if)# ip dvmrp noretransmit

(config-if)# exit

(config)#

ip dvmrp prune-lifetime

Name

ip dvmrp prune-lifetime - specifies the maximum default lifetime of prunes in seconds

Syntax

ip dvmrp prune-lifetime time-seconds

no ip dvmrp prune-lifetime time-seconds?

Mode

Global Configuration

Parameters

time-seconds - an integer value representing a number of seconds ranging from 0 to 2,147,483,648,

inclusive

Description

The ip dvmrp prune-lifetime command configures the maximum value to be placed into a prune

message. The actual lifetime value is the minimum of all the downstream prunes for the source and a randomized value that falls between one-half the prune lifetime and the prune lifetime. The value is in seconds.

The negative form of this command, no dvmrp prune-lifetime, removes the configured time-seconds

value and returns this to its default value of 7200 seconds for neighbors that support Generation ID and 300 seconds for neighbors that do not support Generation ID.

Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

Default

If ip dvmrp prune-lifetime is not specified, it is the same as if the user had specified the following for

neighbors that support Generation ID:

(config)# ip dvmrp prune-lifetime 7200

If ip dvmrp prune-lifetime is not specified, it is the same as if the user had specified the following for

neighbors that do not support Generation ID:

(config)# ip dvmrp prune-lifetime 300

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the prune lifetime to be 7000 seconds.

(config)# ip dvmrp prune-lifetime 7000

ip dvmrp trace file

Distance Vector Multicast Routing Protocol (DVMRP) Page 323

ip dvmrp trace file

Name

ip dvmrp trace file - specifies the file to receive tracing information, the size of the file, whether to

overwrite existing files, and the maximum number of files allowed

Syntax

ip dvmrp trace file file_name [no-timestamp || overwrite]?

no ip dvmrp trace [no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For DVMRP, the ip dvmrp trace file command specifies a file for

tracing of all DVMRP events. The negative form of this command disables this tracing. The specific events

that are traced are controlled by the ip dvmrp trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config)# ip dvmrp trace file /var/log/dvmrp.log no-timestamp

(config)# ip dvmrp trace file /var/log/dvmrp.log

The option given in the second command completely replaces that given in the first. In order to specify both

no-timestamp and max-files 10, they must be entered on the same line as follows.

(config)# ip dvmrp trace file /var/log/dvmrp.log no-timestamp

Default

DVMRP tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, DVMRP tracing is written to the file "/var/tmp/dvmrp.log". No timestamp will display at the beginning of the trace lines.

(config)# ip dvmrp trace file /var/tmp/dvmrp.log no-timestamp

ip dvmrp trace flag

Distance Vector Multicast Routing Protocol (DVMRP) Page 324

ip dvmrp trace flag

Name

ip dvmrp trace flag - specifies DVMRP-specific tracing options as well as options that are common

across all protocols

Syntax

ip dvmrp trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packets | probe | report | prune | graft ] [ send | receive | send-receive ]? [detail?] )

no ip dvmrp trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packets | probe | report | prune | graft ] [ send | receive | send-receive ]? [detail?] )

Mode

Global Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

DVMRP-specific flags:

[ packets | probe | report | prune | graft ] - These DVMRP-specific flags can be associated

with the send, receive, or send-receive action items. These flags are defined as follows:

packets - trace all DVMRP packet types

probe - trace DVMRP probe packets

report - trace DVMRP report packets

prune - trace DVMRP prune packets

graft - trace DVMRP graft packets

[send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the ip dvmrp trace flag command to specify tracing flags for DVMRP tracing. Each flag must reside

on its own configuration line. For example, you cannot specify to trace both probe and prune packets in the same command.

ip dvmrp unicast-routing

Distance Vector Multicast Routing Protocol (DVMRP) Page 325

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received prune and graft messages are traced in detail. This tracing information will be written to the file /var/tmp/dvmrp.log.

(config)# ip dvmrp trace file /var/tmp/dvmrp.log

(config)# ip dvmrp trace flag graft send-receive detail

(config)# ip dvmrp trace flag prune send-receive detail

ip dvmrp unicast-routing

Name

ip dvmrp unicast-routing - configures the interfaces to perform only DVMRP route exchange

Syntax

ip dvmrp unicast-routing

no ip dvmrp unicast-routing

Mode

Interface Configuration

Parameters

none

Description

The ip dvmrp unicast-routing command configures the specified interfaces to perform only DVMRP

route exchange. This is different than the "ip dvmrp" ("ip dvmrp" on page 316) command, which enables

both tree-building operations and routing. When ip dvmrp unicast-routing is configured, the DVMRP

multicast delivery tree-building operations will not be performed on the interface. The negative form of this

command, no ip dvmrp unicast-routing, effectively disables DVMRP, as DVMRP tree-building

operations require DVMRP routing functionality.

Default

Multicast delivery tree-building operations are performed by default. Therefore, if ip dvmrp

unicast-routing is not specified, it is the same as if the user had specified the following: (config-if)# ip-dvmrp unicast-routing

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

This command turns on DVMRP routing.

(config)# interface fxp0

(config-if)# ip dvmrp unicast-routing

show ip dvmrp interfaces

Distance Vector Multicast Routing Protocol (DVMRP) Page 326

(config-if)# exit

(config)#

Example 2

The following example turns on DVMRP routing (no tree building) on the interface. Note what the ip dvmrp

command does: ip dvmrp turns on both DVMRP tree-building and routing. no ip dvmrp will turn off BOTH

DVMRP tree-building and DVMRP routing.

The following sequence of commands can be used to go from BOTH tree-building and routing to just routing.

(config)# interface fxp0

(config-if)# ip dvmrp

(config-if)# end

Both DVMRP tree-building and routing are on as a result of the above commands. Now to migrate to just routing.

(config)# interface fxp0

(config-if)# no ip dvmrp

(config-if)# ip dvmrp unicast-routing

(config-if)# end

show ip dvmrp interfaces

Name

show ip dvmrp interfaces - displays information about the interfaces on which DVMRP is enabled

Syntax

show ip dvmrp interfaces

Mode

User Execution

Parameters

none

Description

The show ip dvmrp interfaces query displays information about all interfaces on which DVMRP is

running.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns information about all interfaces on which DVMRP is enabled.

> show ip dvmrp interfaces

eth1, 192.168.10.1, vif 1, with 3 DVMRP neighbors 5 bad DVMRP packets received, 2 bad DVMRP routes received eth2, 192.168.100.1, vif 2, with 1 DVMRP neighbor 0 bad DVMRP packets received, 0 bad DVMRP routes received

show ip dvmrp neighbors

Distance Vector Multicast Routing Protocol (DVMRP) Page 327

Field Descriptions

The following table describes the fields that appear in the DVMRP Interfaces Query.

Table 20-1 DVMRP Interfaces Query Fields

Field Description

eth1 The physical interface name

192.168.10.1 The IPv4 address used on the interface by the DVMRP protocol

vif The Vif number used to represent this interface to the kernel

DVMRP neighbors The number of DVMRP neighbors reachable on the interface

packets The number of bad DVMRP packets received on the interface

routes The number of bad DVMRP routes received on the interface

show ip dvmrp neighbors

Name

show ip dvmrp neighbors - displays information about this router’s DVMRP neighbors

Syntax

show ip dvmrp neighbors

Mode

User Execution

Parameters

none

Description

The show ip dvmrp neighbors query displays information about all of this router’s DVMRP neighbors.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows information returned for all DVMRP neighbors.

> show ip dvmrp neighbors

192.168.10.1 uptime 01:10:55, expires 00:00:25 via eth0, [version 3.255] [flags: GPM]

show ip dvmrp route

Distance Vector Multicast Routing Protocol (DVMRP) Page 328

192.168.10.2 uptime 01:10:52, expires 00:00:21 via eth0, [version 3.255] [flags: GPM] 192.168.100.1 uptime 02:01:25, expires 00:00:19 via eth1, [version 3.255] [flags: GPM]

Field Descriptions

The following table describes the fields that appear in the DVMRP Neighbors Query.

Table 20-1 DVMRP Neighbors Query Fields

Field Description

192.168.10.1 The DVMRP neighbor address

uptime Length of time the neighbor has been known. Expressed in hours:minutes:seconds.

expires The length of time until the neighbor will be removed unless refreshed. Expressed in hours:minutes:seconds.

via The interface through which the neighbor can be reached

version The DVMRP version of the neighbor router

flags The capabilities of the neighbor router

G: Neighbor supports GenID

P: Neighbor supports prune mechanism

M: Neighbors supports mtrace

show ip dvmrp route

Name

show ip dvmrp route - displays information about the routes in the DVMRP routing table

Syntax

show ip dvmrp route [ipv4-address | interface-name]?

Mode

User Execution

Parameters

ipv4-address - optionally specify a valid IPv4 address in dotted-quad notation

interface-name - optionally specify a physical interface name

show ip dvmrp route

Distance Vector Multicast Routing Protocol (DVMRP) Page 329

Description

The show ip dvmrp route query displays information about the routes in the DVMRP routing table. When

no parameter is given, then information about all DVMRP routes is displayed. When an IPv4 address is given, then information about the best match route is displayed. When a physical interface name is given, then information about only those reached through that interface are displayed.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example returns information about all DVMRP routes.

> show ip dvmrp route

10.5.0.0/16 [70/10] uptime 00:5:45, expires 00:01:10 via 192.168.20.1, fxp3 192.168.10.0/25 [70/5] uptime 01:23:55, expires 00:02:24 via 172.0.0.10, fxp0 192.168.10.1/25 [70/5] uptime 01:23:55, expires 00:02:24 via 172.0.0.20, fxp0

Example 2

The following example returns information for the best match routes to 192.168.10.1.

> show ip dvmrp route 192.168.10.1

DVMRP Routing Table - 1 Entry 192.168.10.0/25 [70/5] uptime 01:23:55, expires 00:02:24 via 172.0.0.10, fxp0

Example 3

The following example returns information about destinations reached through interface fxp0.

> show ip dvmrp route fxp0

DVMRP Routing Table - 1 Entry 192.168.10.0/25 [70/5] uptime 01:23:55, expires 00:02:24 via 172.0.0.10, fxp0 192.168.10.1/25 [70/5] uptime 01:23:55, expires 00:02:24 via 172.0.0.20, fxp0

Field Descriptions

The following table describes the that appear in the DVMRP Route to Source Query.

Table 20-1 DVMRP Route to Source Query Fields

Field Description

192.168.10.0/25 The source network

[70/5] Preference/metric of a route

uptime Length of time the route has been in the routing table. This is expressed in hours:minutes:seconds

tunnel mode dvmrp

Distance Vector Multicast Routing Protocol (DVMRP) Page 330

Field Description

expires Length of time until the route will be removed, unless refreshed. This is expressed in hours:minutes:seconds

via The nexthop router to source network

fxp0 The interface toward the source network

tunnel mode dvmrp

Name

tunnel mode dvmrp - configures Advanced Routing Suite to perform old-style DVMRP tunnel

encapsulation

Syntax

tunnel mode dvmrp

no tunnel mode dvmrp

Mode

Interface Configuration

Parameters

none

Description

The tunnel mode dvmrp command configures Advanced Routing Suite to perform old-style DVMRP tunnel

encapsulation. In old-style tunnel encapsulation, DVMRP control messages are non ip-ip encapsulated, but merely unicasted to the tunnel endpoint.

Default

If tunnel mode dvmrp is not specified, it is the same as if the user had specified the following: (config-if)# no tunnel mode dvmrp

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a tunnel is configured on logical interface 192.168.15.1 with a remote end point of 192.168.10.1. DVMRP tunnel mode is then enabled on the tunnel.

(config)# ipip-tunnel 192.168.15.1 192.168.10.1

(config)# interface 192.168.10.1

(config-if)# tunnel mode dvmrp

(config-if)# exit

(config)#

tunnel mode dvmrp

Distance Vector Multicast Routing Protocol (DVMRP) Page 331

Page 332

Chapter 16

Internet Group Management Protocol (IGMP)

In This Chapter

Internet Group Management Protocol (IGMP) Overview 332

clear ip igmp group 333

ip igmp 334

ip igmp ignore-v1-messages 335

ip igmp ignore-v2-messages 335

ip igmp last-member-query-count 336

ip igmp last-member-query-interval 337

ip igmp query-interval 339

ip igmp query-max-response-time 340

ip igmp require-router-alert 341

ip igmp robustness 342

ip igmp send-router-alert 343

ip igmp startup-query-count 344

ip igmp startup-query-interval 345

ip igmp static-group 347

ip igmp trace file 348

ip igmp trace flag 349

ip igmp version 350

show ip igmp groups 351

show ip igmp interface 355

show ip igmp interface-summary 358

show ip igmp static-groups 359

Internet Group Management Protocol (IGMP) Overview

IGMP was designed for hosts on multi-access networks to inform locally-attached routers of their multicast group memberships. Hosts inform routers of the groups of which they are members by multicasting IGMP Group Membership Reports. Once multicast routers listen for these reports, they can exchange group membership information with other multicast routers. This reporting system allows distribution trees to be formed to deliver multicast datagrams. The original version of IGMP was defined in RFC 1112, Host Extensions for IP Multicasting. Extensions to IGMP, known as IGMP version 2, include explicit Leave messages for faster pruning and are defined in RFC 2236. Advanced Routing Suite implements IGMP version 2, which includes interoperability with version 1 hosts, and version 3, which includes interoperability with version 2 and version 1 hosts. The original version of IGMP can be found at:

http://www.ietf.org/rfc/rfc1112.txt

IGMP version 2 is described in:

http://www.ietf.org/rfc/rfc2236.txt

clear ip igmp group

Internet Group Management Protocol (IGMP) Page 333

IGMP version 3 is described in:

http://www.ietf.org/rfc/rfc3376.txt

clear ip igmp group

Name

clear ip igmp group - removes IGMP join state

Syntax

clear ip igmp group [ group-name || group-address || type || number ]?

Mode

Privileged Execution

Parameters

group-name - the name of the multicast group, as defined in DNS host table. Entering this is optional.

group-address - the IPv4 address of the multicast group in dotted-quad format. Entering this is optional.

type - the interface type. Entering this is optional.

number - the interface number. Entering this is optional.

Description

Use clear ip igmp group to remove IGMP join state. This command has four forms, depending upon

whether any or all of the optional parameters are provided. If only the group name or group address is specified, then the associated group entries will be deleted from all interfaces. If only the interface is specified, then all group entries will be deleted for the interface. If neither a group nor an interface is specified, then group memberships over all the IGMP interfaces will be deleted.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example shows a request to clear group entry for 224.1.1.1 on interface 192.168.10.1.

# clear ip igmp group 224.1.1.1 192.168.10.1

Example 2

The following example shows a request to clear group entries for interface Ethernet0/1.

# clear ip igmp group Ethernet0/1

Example 3

The following example shows a request to clear group entries for group 224.1.1.1 on interface Ethernet0/1.

# clear ip igmp group 224.1.1.1 Ethernet0/1

Example 4

The the following example, a request is issued to clear the same group entries for group 224.1.1.1 on interface Ethernet0/1, as in Example 3. The difference is that in this example, the interface is specified first, followed by the group.

# clear ip igmp group Ethernet0/1 224.1.1.1

ip igmp

Internet Group Management Protocol (IGMP) Page 334

Example 5

The following example issues a request to clear group entry without any parameters. This essentially deletes all group entries over all interfaces.

# clear ip igmp group

ip igmp

Name

ip igmp - enables or disables the IGMP protocol

Syntax

ip igmp

no ip igmp

Mode

Interface Configuration

Parameters

none

Description

The ip igmp configuration enables the IGMP protocol on the associated interface with the default set of

configurations. Its "no" form (no ip igmp) disables IGMP on the interface.

Default

IGMP is not run on interfaces by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example enables IGMP on interface fxp1 only.

(config)# interface fxp1

(config-if)# ip igmp

Example 2

With the command line still in Interface Configuration Mode for interface fxp1, the following example disables IGMP on that interface.

(config-if)# no ip igmp

(config-if)# exit

(config)#

ip igmp ignore-v1-messages

Internet Group Management Protocol (IGMP) Page 335

ip igmp ignore-v1-messages

Name

ip igmp ignore-v1-messages - specifies whether to process IGMPv1 messages on the associated

interface(s)

Syntax

ip igmp ignore-v1-messages

no ip igmp ignore-v1-messages

Mode

Interface Configuration

Parameters

none

Description

The ip igmp ignore-v1-messages configuration disables processing of all IGMPv1 messages on the

associated interface. Note that this breaks interoperability with older IGMPv1 speakers on the network and should be done when it is important to maintain small group leave latencies.

Note: This configuration is meaningful only when the current version on the interface is IGMPv2 or IGMPv3.

A warning will be given if you attempt to configure ignore-v1-messages and the current version is

IGMPv1.

The negative form of this command resets the option such that IGMPv1 messages are not ignored.

Default

If ignore-v1-messages is not configured, it is the same as if the user had specified the following: (config-if)# no ip igmp ignore-v1-messages

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, ip igmp ignore-v1-messages is used to disable processing of IGMPv1

messages on interface fxp0.

(config)# interface fxp0

(config-if)# ip igmp ignore-v1-messages

(config-if)# exit

(config)#

ip igmp ignore-v2-messages

Name

ip igmp ignore-v2-messages - specifies whether to process IGMPv2 messages on the associated

interface(s)

Syntax

ip igmp ignore-v2-messages

ip igmp last-member-query-count

Internet Group Management Protocol (IGMP) Page 336

no ip igmp ignore-v2-messages

Mode

Interface Configuration

Parameters

none

Description

The ip igmp ignore-v2-messages configuration disables processing of all IGMPv2 messages on the

associated interface. Note that this breaks interoperability with older IGMPv2 speakers on the network and should be done when it is important to maintain small group leave latencies.

Note: This configuration is meaningful only when the current version on the interface is IGMPv3. A warning

will be given if you attempt to configure ignore-v2-messages and the current version is not IGMPv3.

The negative form of this command resets the option such that IGMPv2 messages are not ignored.

Default

If ignore-v2-messages is not configured, it is the same as if the user had specified the following: (config-if)# no ip igmp ignore-v2-messages

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, ip igmp ignore-v2-messages is used to disable processing of IGMPv1

messages on interface fxp0.

(config)# interface fxp0

(config-if)# ip igmp ignore-v2-messages

(config-if)# exit

(config)#

ip igmp last-member-query-count

Name

ip igmp last-member-query-count - specifies the number of queries sent out on startup, separated by

the Last Member Query Interval

Syntax

ip igmp last-member-query-count value

no ip igmp last-member-query-count value?

Mode

Global Configuration

Interface Configuration

Parameters

value - an integer between 1 and 65535, inclusive

ip igmp last-member-query-interval

Internet Group Management Protocol (IGMP) Page 337

Description

The command configures the value of the Last Member Query Count as specified in RFC 3376. It specifies the number of queries sent out on startup, separated by the Last Member Query Interval.

The last-member-query-count and its no form configuration can be issued in both Global Configuration

and Interface Configuration modes. If this is configured in Global Configuration mode, then it configures the default Last Member Query Count for all interfaces over which IGMP is running. If it is configured in Interface Configuration mode, then it configures the Last Member Query Count for the associated interfaces.

Use the no form of the configuration to return to the default last-member-query-count value. Note:

Specifying a value in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If an interface-scoped last-member-query-count is configured, then that configured value is used on

the interface. If an interface-scoped last-member-query-count is not configured, then the value used

on the interface is the value specified in an interface-scoped robustness. If an interface-scoped

robustness is not configured, then the value used on the interface is the value specified in the globally

scoped last-member-query-count. If no globally scoped last-member-query-count is configured,

then the value used on the interface is the value of the globally scoped robustness. Finally, if no globally

scoped robustness is configured, then the value used on the interface is 2.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the Last Member Query Count to be 4.

(config)# ip igmp last-member-query-count 4

Example 2

In the following example, the globally scoped Robustness is configured to be 4. The globally scoped Last Member Query count is configured to be 5. Neither the interface-scoped Robustness nor the

interface-scoped Last Member Query Count is configured for interface fxp1. The no ip igmp

startup-query-count for fxp1 implies that the globally scoped Last Member Query Count value of 5 will

be used on that interface.

(config)# ip igmp robustness 4

(config)# ip igmp last-member-query-count 5

(config)# interface fxp1

(config-if)# no ip igmp startup-query-count

(config-if)# exit

(config)#

ip igmp last-member-query-interval

Name

ip igmp last-member-query-interval - specifies the maximum amount of time that hosts are allowed

to respond to Group-Specific query messages

Syntax

ip igmp last-member-query-interval time-milliseconds

no ip igmp last-member-query-interval time-milliseconds?

ip igmp last-member-query-interval

Internet Group Management Protocol (IGMP) Page 338

Mode

Global Configuration

Interface Configuration

Parameters

time-milliseconds - specifies a number of milliseconds. This value can be either 0 or an integer from

1000 to 31744000, inclusive.

Description

The ip igmp last-member-query-interval command configures the length of the Last Member

Query Interval - the interval determining the maximum amount of time that hosts are given to respond to Group-Specific or Group-and-Source-Specific queries. This value is encoded in the Max Resp Code field of Group-Specific or Group-and-Source-Specific Query messages and can be either 0 or an integer from 1000 to 31744000, inclusive. Note: The value range 1 to 999 is not permitted.

The Last Member Query Interval configuration and its no form can be issued in both Global Configuration and Interface Configuration modes. If this is configured in Global Configuration mode, then it configures the default Last Member Query Interval for all interfaces over which IGMP is running. If this is configured in Interface Configuration mode, then it configures the Last Member Query Interval for the associated interfaces.

Use the no form of this configuration to return to the default value of the Last Member Query Interval. Note:

Specifying a value for time-milliseconds in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

Default

If ip igmp last-member-query-interval is not specified, it is the same as if the user had entered the

following:

(config)# ip igmp last-member-query-interval 1000 or (config-if)# ip igmp last-member-query-interval 1000

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the default Last Member Query Interval to be 2000 milliseconds (20 seconds)

(config)# ip igmp last-member-query-interval 2000

Example 2

The following example configures the default Last Member Query Interval to be 3000 milliseconds. This value is then overridden in interface fxp0, where it is configured to be 2000 milliseconds. The no ip igmp last-member-query-interval for interface fxp1 implies that the configured default value of 3000 will be used on that interface.

(config)# ip igmp last-member-query-interval 3000

(config)# interface fxp0

(config-if)# ip igmp last-member-query-interval 2000

(config-if)# exit

(config)# interface fxp1

(config-if)# no ip igmp last-member-query-interval

(config-if)# exit

ip igmp query-interval

Internet Group Management Protocol (IGMP) Page 339

(config)#

ip igmp query-interval

Name

ip igmp query-interval - specifies the value of the query interval in seconds

Syntax

ip igmp query-interval time-seconds

no ip igmp query-interval time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - specifies a number in seconds between 1 and 3174, inclusive. Note: This value cannot be

less than the Query Response Interval.

Description

This command specifies the value of the Query Interval in seconds. The Query Interval is the interval between General Queries sent by the Querier. It is encoded in the Query Interval Code (QQIC) field of

General Queries. The Query Interval cannot be less than the Query Response Interval (configured using ip

igmp query-response-interval). The maximum value of the Query Interval is 3174 seconds.

The Query Interval configuration and its no form configuration can be issued in both Global Configuration Mode and Interface Configuration Mode. If it is configured in Global Configuration Mode, it configures the default Query Interval for all interfaces over which IGMP is running. If it is configured in Interface

Configuration Mode (in other words, at the (config-if)# prompt), then it configures the Query Interval for

the associated interfaces.

Use the no form of the configuration to return to the default value of 125 seconds. Note: Specifying a value

for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If ip igmp query-interval is not specified, it is the same as if the user had specified the following: (config)# ip igmp query-interval 125 or (config-if)# ip igmp query-interval 125

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the default Query Interval for all interfaces to be 200 seconds.

(config)# ip igmp query-interval 200

Example 2

The following example configures the default Query Interval to be 200 seconds and the Query Interval for interface fxp0 to be 210 seconds. The no igmp query-interval command for fxp1 implies that the configured default value of 200 seconds will be used on that interface.

ip igmp query-max-response-time

Internet Group Management Protocol (IGMP) Page 340

(config)# ip igmp query-interval 200

(config)# interface fxp0

(config-if)# ip igmp query-interval 210

(config-if)# exit

(config)# interface fxp1

(config-if)# no ip igmp query-interval

ip igmp query-max-response-time

Name

ip igmp query-max-response-time - configures the maximum amount of time allowed before a host

sends a report message

Syntax

ip igmp query-max-response-time time-seconds

no ip igmp query-max-response-time time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - a number between 0 and 3174 seconds, inclusive. Note: This value must be less than or

equal to the Query Interval.

Description

The ip igmp query-max-response-time command configures the length of the Query Response

Interval, the maximum amount of time allowed before a Host sends a Report message in response to a received General Query. This interval is encoded in the Max Resp Code field of General Query messages. The interval can have a value from 0 to 3174 seconds. This value must be less than or equal to the Query Interval.

The ip igmp query-max-response-time command and its no form can be issued in both Global

Configuration Mode and Interface Configuration Mode. When issued in Global Configuration Mode, it configures the default Query Response Interval for all interfaces over which IGMP is running. If it is configured in Interface Configuration Mode, it configures the Query Response Interval for the associated interfaces.

Use the no form of the configuration to return to the default value of 10 seconds. Note: Specifying a value

for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as

optional.

Note: There is forward and backward conversion between the Advanced Routing Suite CLI and the Advanced Routing Suite XML for this item. The equivalent XML command,

<query-response-interval>, is configured in units of deciseconds. When this value is configured in

the Advanced Routing Suite CLI, the CLI converts it from seconds to deciseconds before sending the configuration to XML. Then, in show running, the CLI receives deciseconds from the XML configurator and converts it back to seconds, rounding it down to the nearest second. For example, if this value is configured in XML as 31712 deciseconds, then it will be read in the CLI as 3171 seconds.

Default

If ip igmp query-max-response-time is not specified, it is the same as if the user had specified the following:

ip igmp require-router-alert

Internet Group Management Protocol (IGMP) Page 341

(config)# ip igmp query-max-response-time 10 or (config-if)# ip igmp query-max-response-time 10

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the default Query Response Interval to be 10 seconds (or 100 deciseconds).

(config)# ip igmp query-max-response-time 100

Example 2

The following example configures the default Query Response Interval to be 11 seconds and the Query

Response Interval for interface fxp0 to be 12 seconds. The no ip igmp query-max-response-time

command for fxp1 implies that the configured default value of 110 deciseconds will be used on that interface.

(config)# ip igmp query-max-response-time 110

(config)# interface fxp0

(config-if)# ip igmp query-max-response-time 120

(config-if)# exit

(config)# interface fxp1

(config-if)# no ip igmp query-max-response-time

ip igmp require-router-alert

Name

ip igmp require-router-alert - specifies whether to ignore messages that do not contain the Router

Alert option, thereby improving protocol security

Syntax

ip igmp require-router-alert

no ip igmp require-router-alert

Mode

Global Configuration

Interface Configuration

Parameters

none

Description

The require-router-alert configuration specifies whether to ignore messages that do not container

the Router Alert option, thereby improving protocol security. If this command is configured, then the following messages are ignored if they do not contain the Router Alert option:

State-Change Report

Current-State Report

ip igmp robustness

Internet Group Management Protocol (IGMP) Page 342

Leave Message in IGMP version 2 mode

Report Message in IGMP version 2 mode

This configuration and its no form configuration can be issued in both Global Configuration and Interface Configuration modes. If this is configured in Global Configuration mode, then it configures the default for all interfaces over which IGMP is running. If it is configured in Interface Configuration mode, then it configures the parameter for the associated interfaces.

Use the no form configuration to return to the default value.

Default

If require-router-alert is not specified, it is the same as if the user had specified the following:

(config)# ip igmp require-router-alert or (config-if)# ip igmp require-router-alert

Command History

NGC 2.2 - This command was introduced.

NGC 2.3 - The default for this command changed from off to on.

Examples

The following example turns require-router-alert off for interface fxp0 and on for all other interfaces.

(config)# interface fxp0

(config-if)# no ip igmp require-router-alert

(config-if)# exit

(config)# ip igmp require-router-alert

ip igmp robustness

Name

ip igmp robustness - allows for tuning of the IGMP protocol or interface to accommodate a lossy subnet

Syntax

ip igmp robustness value

no ip igmp robustness value?

Mode

Global Configuration

Interface Configuration

Parameters

value - an integer between 2 and 7, inclusive

Description

The ip igmp robustness command allows you to tune IGMP for the expected loss on a network. IGMP is

robust to (Robustness - 1) packet losses, and this value is advertised in the Querier’s Robustness Variable (QRV) field of Query.

The ip igmp robustness configuration and its no form can be issued in both Global Configuration and

Interface Configuration modes. If this command is configured in Global Configuration mode, it configures the default Robustness for all interfaces over which IGMP is running. If it is configured in Interface Configuration mode, it configures the Robustness for the associated interfaces.

ip igmp send-router-alert

Internet Group Management Protocol (IGMP) Page 343

Use the no form of this configuration to return to the default value of Robustness. Note: Specifying a value

in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip igmp robustness is not specified, it is the same as if the user had specified the following:

(config)# ip igmp robustness 2 or (config-if)# ip igmp robustness 2

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the default Robustness to be 3.

(config)# ip igmp robustness 3

Example 2

The following example configures the default Robustness to be 3 and the Robustness for interface fxp0 to be 4. The no ip igmp robustness for interface fxp1 implies that the configured default value of 3 will be used on that interface.

(config)# ip igmp robustness 3

(config)# interface fxp0

(config-if)# ip igmp robustness 4

(config-if)# exit

(config)# interface fxp1

(config-if)# no ip igmp robustness

ip igmp send-router-alert

Name

ip igmp send-router-alert - specifies whether sent IGMP packets will include the Router Alert option

in the IP packet header

Syntax

ip igmp send-router-alert

no ip igmp send-router-alert

Mode

Global Configuration

Interface Configuration

Parameters

none

Description

Use the ip igmp send-router-alert option to specify that sent packets should include the router alert

option in the IP packet header.

ip igmp startup-query-count

Internet Group Management Protocol (IGMP) Page 344

Default

If ip igmp send-router-alert is not specified, it is the same as if the user had specified the following: (config)# no ip igmp send-router-alert or (config-if)# no ip igmp send-router-alert

Command History

NGC 2.2 - This command was introduced.

Examples

The following example turns the send-router-alert option on for all of IGMP, then explicitly turns it off for interface fxp1.

(config)# ip igmp send-router-alert

(config)# interface fxp1

(config-if)# no ip igmp send-router-alert

(config-if)# exit

(config)#

ip igmp startup-query-count

Name

ip igmp startup-query-count - specifies the number of queries sent out on startup, separated by the

Startup Query Interval

Syntax

ip igmp startup-query-count value

no ip igmp startup-query-count value?

Mode

Global Configuration

Interface Configuration

Parameters

value - an integer between 1 and 65535, inclusive

Description

This configuration specifies the value of the Startup Query Count as specified in RFC 236 and RFC 3376. It configures the number of queries sent out on startup, separated by the Startup Query Interval. The number of queries can be an integer between 1 and 65535, inclusive.

This configuration, and its no form configuration can be issued in both Global Configuration and Interface

Configuration modes. If this is configured in Global Configuration mode, then it configures the default Startup Query Count for all interfaces over which IGMP is running. If it is configured in Interface Configuration mode, then it configures the Startup Query Count for the associated interfaces.

Use the no form of this configuration to return to the default value of Startup Query Count. Note: Specifying

a value in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If an interface-scoped startup-query-count is configured, then the configured value is used on the

interface.If an interface-scoped startup-query-count is not configured, then the value used on the

interface is the value specified in an interface-scoped robustness. If an interface-scoped robustness is

ip igmp startup-query-interval

Internet Group Management Protocol (IGMP) Page 345

not configured, then the value used on the interface is the value specified in the globally scoped

startup-query-count. If no globally scoped startup-query-count is configured, then the value

used on the interface is the value of the globally scoped robustness. Finally, if no globally scoped

robustness is configured, then the value used on the interface is 2.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the globally scoped Startup Query Count to be 4.

(config)# ip igmp startup-query-count 4

Example 2

In the following example, the globally scoped Robustness value is configured to be 4. The no ip igmp

startup-query-count for interface fxp1 implies that the globally scoped Robustness value of 4 will be

used on that interface.

(config)# ip igmp robustness 4

(config)# interface fxp1

(config-if)# no ip igmp startup-query-count

(config-if)# exit

(config)#

ip igmp startup-query-interval

Name

ip igmp startup-query-interval - specifies the time between successive General Query messages

on startup.

Syntax

ip igmp startup-query-interval time-deciseconds

no ip igmp startup-query-interval time-deciseconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-deciseconds - a number in tenths of a second between 10 and 317440

Description

This command configures the value of the Startup Query Interval as specified in RFC3376. This parameter determines the time between successive General Query messages on startup. This value is expressed in units of deciseconds (1/100 of a second) and is encoded in the Max Resp Code field of Query messages. The range of this parameter is 10 to 317440 deciseconds. All values between 10 and 1270 deciseconds are exactly configurable. Above 1270 deciseconds, only intervals for which integer values of 'e' and 'm' exist to satisfy the equation below are exactly configurable.

interval = (16 + m) * 2^(e + 3)

where

ip igmp startup-query-interval

Internet Group Management Protocol (IGMP) Page 346

0 <= e <= 7

0 <= m <= 15

If no values of m and e exist to exactly represent the configured value, then Advanced Routing Suite will round down to the next lower, representable value is used.

The Startup Query Configuration and its no form configuration can be issued in both Global Configuration

and Interface Configuration modes. If this is configured in Global Configuration mode, then it configures the default Startup Query Interval for all interfaces over which IGMP is running. If this is configured in Interface Configuration mode, then it configures the Startup Query Interval for the associated interface.

Use the no form of this configuration to return to the default value of Startup Query Interval. Note:

Specifying a value for deciseconds in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Default

If an interface-scoped startup-query-interval is configured, then the configured value is used on the

interface. If an interface-scoped startup-query-interval is not configured, then the value used on the

interface is one-fourth (1/4) the value specified in an interface-scoped query-interval. If an

interface-scoped query-interval is not configured, then the value used on the interface is the value

specified in the globally scoped startup-query-interval. If no globally scoped

startup-query-interval is configured, then the value used on the interface is one-fourth the value of

the globally scoped query-interval. Finally, if no globally scoped query-interval is configured, then

the value used on the interface is 31 seconds.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the default Startup Query Interval to be 120 deciseconds (12 seconds).

(config)# ip igmp startup-query-interval 120

Example 2

The the following example, the default Startup Query Interval is configured to be 120 deciseconds. The

Startup Query Interval for interface fxp0 is configured to be 110 deciseconds. The no ip igmp

startup-query-interval for fxp1 implies that the globally scoped Startup Query Interval value of 120

will be used on that interface.

(config)# ip igmp startup-query-interval 120

(config)# interface fxp0

(config-if)# ip igmp startup-query-interval 110

(config-if)# exit

(config)# interface fxp1

(config-if)# no ip igmp startup-query-interval

Example 3

In the following example, an attempt is made to configure the Startup Query Interval for fxp0 to 274. No values of m and e satisfy the equation below.

247 = (16 + m) * 2^(e + 3)

Therefore, the value that Advanced Routing Suite will actually use will be the next lowest representable value, 272 (m = 1, e = 1)

Attempted configuration:

(config)# interface fxp0

ip igmp static-group

Internet Group Management Protocol (IGMP) Page 347

(config-if)# ip igmp startup-query-interval 274

(config-if)# exit

(config)#

See Also

"ip igmp query-interval" ("ip igmp query-interval" on page 339)

ip igmp static-group

Name

ip igmp static-group - causes the router to establish a static join to the multicast group

Syntax

ip igmp static-group group-address [ source source-address ]?

no ip igmp static-group group-address [ source source-address ]?

Mode

Interface Configuration

Parameters

group group-address - a valid multicast group address in dotted-quad notation

source source-address - a valid multicast source addresses in dotted-quad notation. Specifying this is

optional. Note that when specifying a source address, the source keyword is required.

Description

The ip igmp static-group command causes the router to establish a static join to the multicast group.

Note that the group is not actually joined. In other words, no IGMP messages are triggered in response to this command. Instead, this command causes multicast routing to behave as if there were a local member of the indicated group (and source) reachable via the associated interface.

The group-address value is the address of the multicast group in dotted-quad notation. The source

keyword allows you to specify a (source, group) pair to be forwarded out of the interface if the group is within the SSM range.

Use the negative form of this command, no ip igmp static-group, to cancel a static join for a multicast

group.

Default

none

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the router to join group 224.1.1.1 on interface fxp0.

(config)# interface fxp0

(config-if)# ip igmp static-group 224.1.1.1

(config-if)# exit

(config)#

ip igmp trace file

Internet Group Management Protocol (IGMP) Page 348

Example 2

In the following example, the router is configured to cancel its membership for group 224.1.1.1.

(config)# interface fxp0

(config-if)# no ip igmp static-group

(config-if)# exit

(config)#

Example 3

In the following example, the router is configured to forward packets from source 192.168.11.1 for group 232.1.1.1 on interface fxp0.

(config)# interface fxp0

(config-if)# ip igmp static-group 232.1.1.1 source 192.168.11.1

(config-if)# exit

(config)#

ip igmp trace file

Name

ip igmp trace file - specifies file options when tracing in IGMP

Syntax

ip igmp trace file file_name [no-timestamp || overwrite]?

no ip igmp trace file name file_name [no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. For IGMP, the ip igmp trace file command specifies a file for

tracing of all IGMP events. The negative form of this command disables this tracing. The specific events that

are traced are controlled by the ip igmp trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config)# ip igmp trace file /var/log/igmp.log no-timestamp

(config)# ip igmp trace file /var/log/igmp.log

The option given in the second command completely replaces that given in the first.

ip igmp trace flag

Internet Group Management Protocol (IGMP) Page 349

Default

IGMP tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, IGMP tracing is written to the file "/var/tmp/igmp.log"(config)# ip igmp trace file /var/tmp/igmp.log

ip igmp trace flag

Name

ip igmp trace flag - specifies IGMP-specific tracing options as well as options that are common across

all protocols

Syntax

ip igmp trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ query | report | leave | packets ] [ send | receive | send-receive ]? [detail?] )

no ip igmp trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ query | report | leave | packets ] [ send | receive | send-receive ]? [detail?] )

Mode

Global Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

IGMP-specific flags:

[ leave | query | report | packets ] - The IGMP-specific flags can be associated with the send,

receive, or send-receive action items. These flags are defined as follows:

leave - trace all IGMPv3 Leave messages.

query - trace IGMPv3 Membership Query messages.

report - trace IGMPv3 Membership Report messages.

packets - trace all IGMPv3 packets

ip igmp version

Internet Group Management Protocol (IGMP) Page 350

[ send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the ip igmp trace flag command to specify tracing flags for IGMP tracing. Each flag must reside on

its own configuration line. For example, you cannot specify to trace both query and leave packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received query and report messages are traced in detail. This tracing information will be written to the file /var/tmp/igmp.log.

(config)# ip igmp trace file /var/tmp/igmp.log

(config)# ip igmp trace flag query send-receive detail

(config)# ip igmp trace flag report send-receive detail

ip igmp version

Name

ip igmp version - specifies the version of IGMP to run

Syntax

ip igmp version [ 1 | 2 | 3 ]

no ip igmp version

Mode

Interface Configuration

Parameters

1 | 2 | 3 - specifies whether to run version 1, version 2, or version 3 of IGMP

Description

Use the ip igmp version configuration to specify the version of IGMP that you want to run.

Default

If ip igmp version is not specified, it is the same as if the user had specified the following:

(config-if)# ip igmp version 3

Command History

NGC 2.2 - This command was introduced.

show ip igmp groups

Internet Group Management Protocol (IGMP) Page 351

Examples

The following example configures IGMP version 2 to run on interface fxp0.

(config)# interface fxp0

(config-if)# ip igmp version 2

(config-if)# exit

(config)#

show ip igmp groups

Name

show ip igmp groups - displays IGMP information regarding multicast group membership

Syntax

show ip igmp groups [group-name || interface (ipv4_address | interface_name)] [detail]?

show ip igmp groups [group-address || interface (ipv4_address | interface_name)] [detail]?

Mode

Privileged Execution

Parameters

group-name - the name of the multicast group, as defined in DNS host table. If a group-name is specified,

an optional interface can also be specified to view group information for that interface.

group-address - the IPv4 address of the multicast group in dotted-quad format. Entering this is optional. If

a group-address is specified, an optional interface can also be specified to view group information for that interface.

interface (ipv4_address | interface_name) - optionally specify to view information for a specific

interface or for a specific interface within a specific group

detail - displays IGMPv3 style group information and source information. Entering this is optional.

Otherwise, IGMPv2 style group information is given.

Description

Use show ip igmp groups to obtain IGMP information regarding multicast group membership. Queries

can be submitted in multiple forms, as shown in the examples that follow. If a query is issued without specifying a group, then group membership information for all groups that are connected to this router will be returned. Alternatively, a query can be issued with the name of the multicast group, the IPv4 address of

the multicast group, and/or the interface specified, with or without the detail option. If detail is specified,

the response will contain IGMPv3 specific information, including the group mode and other source information.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example queries information pertaining to IGMP or all groups on all interfaces.

# show ip igmp groups

show ip igmp groups

Internet Group Management Protocol (IGMP) Page 352

IGMP Connected Group Membership Group Address Interface Uptime Expires Last Reporter 224.1.1.1 fxp1 00:00:32 00:01:32 10.2.25.159 224.1.1.1 fxp0 00:00:33 00:01:33 10.2.12.31 224.1.1.2 fxp0 00:00:32 00:01:32 10.2.12.31 224.1.1.3 fxp1 00:00:31 00:01:31 10.2.25.159

Example 2

The following example is a query for group information pertaining to IGMP for multicast group 224.1.1.1.

# show ip igmp groups 224.1.1.1

IGMP Connected Group Membership Group Address Interface Uptime Expires Last Reporter 224.1.1.1 fxp1 00:01:30 00:02:30 10.2.25.159 224.1.1.1 fxp0 00:01:31 00:02:31 10.2.12.31

Example 3

The following query requests group information pertaining to IGMP for interface eth1.

# show ip igmp groups interface eth1

IGMP Connected Group Membership Group Address Interface Uptime Expires Last Reporter 224.1.1.1 fxp0 00:02:20 00:03:20 10.2.12.31 224.1.1.2 fxp0 00:02:19 00:03:19 10.2.12.31

Example 4

The following query is a request for group information pertaining to group 224.1.1.1 on interface eth1.

# show ip igmp groups 224.1.1.1 interface eth1

IGMP Connected Group Membership Group Address Interface Uptime Expires Last Reporter 224.1.1.1 fxp0 00:02:57 00:03:57 10.2.12.31

Example 5

The following example is a query for group information pertaining to IGMP in detail for all groups on all interfaces.

# show ip igmp groups detail

IGMP connected Group Membership Interface: Ethernet0/1 (192.168.11.1) Group: 224.1.1.1 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.11.2 Last-member-query-counter: 1 Last-member-query-timer-expiry: off Group mode: EXCLUDE Version1-host-present-timer-expiry: 00:00:20 Version2-host-present-timer-expiry: off Source list is empty

Interface: Ethernet0/2 (192.168.12.1) Group: 224.2.2.2 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.12.2 Last-member-query-timer-expiry: off Group mode: EXCLUDE Version1-host-present-timer-expiry: 00:00:20 Version2-host-present-timer-expiry: off Source list is empty

show ip igmp groups

Internet Group Management Protocol (IGMP) Page 353

Interface: Etherent0/2 (192.168.13.1) Group: 224.3.3.3 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.13.2 Last-member-query-counter: 0 Last-member-query-timer-expiry: off Group mode: INCLUDE Version1-host-present-timer-expiry: 00:00:20 Version2-host-present-timer-expiry: off Source list: Source: 10.1.1.1 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.13.2 Last-member-query-counter: 0 Last-member-query-timer-expiry: off

Source: 10.11.11.11 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.13.2 Last-member-query-counter: 1 Last-member-query-timer-expiry: 00:00:05

Example 6

In the following example, group information pertaining to group 224.1.1.1 on interface eth3, in detail, is requested.

# show ip igmp groups 224.1.1.1 interface eth3 detail

IGMP connected Group Membership Interface: Ethernet0?1 (192.168.13.2) Group: 224.1.1.1 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.13.2 Last-member-query-counter: 0 Last-member-query-timer-expiry: off Group mode: INCLUDE Version1-host-present-timer-expiry: 00:00:20 Version2-host-present-timer-expiry: off Source list Source: 10.3.3.3 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.13.2 Last-member-query-counter: 0 last-member-query-timer-expiry: off

Source: 10.33.33.33 Uptime: 00:00:34 Expires: 00:00:40 Last reporter: 192.168.13.2 Last-member-query-counter: 1 Last-member-query-timer-expiry: 00:00:02

Example 7

In the following example, group information in details pertaining to group 224.1.1.1 on interface eth3 is requested. The response indicates that IGMP is not running on the router.

# show ip igmp groups 224.1.1.1 interface eth3 detail

IGMP is not running.

show ip igmp groups

Internet Group Management Protocol (IGMP) Page 354

Field Descriptions

The following table describes the fields that appear in the IGMP Group Information Query.

Table 21-1 IGMP Group Information Query Fields

Field Description

Group The IPv4 address of the multicast group

Interface The interface through which the group has been joined

Uptime The length of time, in hours, minutes, and seconds, that this multicast group has been learned

Expires The length of time, in hours, minutes, and seconds, until the entry is to be removed from the group table

Last Reporter The last host that reported being a member of the multicast group

Last-member-query-counter The remaining number of group-specific or group-and-source specific queries to be sent over the interface for the group or source

Last-member-query-timer-expiry The length of time in hours, minutes, and seconds until the next group-specific or group-and-source specific query is to be sent

Group mode The router filter mode for the group

Version1-host-present-timer-expiry The length of time in hours, minutes, and seconds until the Version 1 Host Present Timer will expire

Version2-host-present-timer-expiry The length of time in hours, minutes, and seconds until the Version 2 Host Present Timer will expire

Source The IPv4 address of the source

show ip igmp interface

Internet Group Management Protocol (IGMP) Page 355

show ip igmp interface

Name

show ip igmp interface - displays multicast-related information about a specific interface or all

interfaces

Syntax

show ip igmp interface [ interface-name | ipv4_address ]?

Mode

User Execution

Parameters

interface-name - optionally specify a physical interface

ipv4_address - optionally specify the logical interface address

Description

The show ip igmp interface query displays multicast-related information about a specific interface or all

interfaces.

This query has two forms. If the query is issued without arguments, then information on about all interfaces over which IGMP is running is returned. Alternatively, the query can be issued with a specific interface. If this is the case, then the reply will contain information pertaining only to that referenced interface.

Note that if interfaces are added to the set of interfaces over which IGMP is running after this query has been issued but before the query is finished, it is not guaranteed that the new interfaces will be reported. Similarly, if IGMP is de-configured on an interface after the query has been issued but before the query is finished, then the interface may or may not be reported.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example displays interface information for all interfaces on which IGMP is running.

# show ip igmp interface

eth0 is up Internet address: 10.129.10.26/9 IGMP on this interface: disabled Multicast routing on this interface: disabled Multicast TTL threshold: 0 Multicast groups joined: 0

eth1 is up Internet address: 192.168.11.1/24 IGMP on this interface: enabled Current IGMP router version: 2 IGMP query interval: 60 seconds IGMP max query response time: 10 seconds Last member query response interval: 1000 ms IGMP activity: 1 joins, 0 leaves Multicast routing on this interface: enabled Multicast TTL threshold: 0 Multicast designated router (DR): 192.168.11.1 (this system) IGMP Querier: 192.168.11.1 (this system)

show ip igmp interface

Internet Group Management Protocol (IGMP) Page 356

Robustness: 2 Require-router-alert: no Last-member-query-interval: 30 deciseconds Startup-query-interval: 300 deciseconds Startup-query-count: 2 General-query-timer-expiry: 00:00:20 (hours:minutes: seconds) Startup-query-timer-expiry: off Other-querier-present-timer-expiry: off Multicast groups joined (number of users): 224.0.0.2(1) 224.1.1.1(1)

fxp0 is up Internet address: 192.168.12.1/24 IGMP on this interface: enabled Current IGMP router version: 3 IGMP query interval: 125 seconds IGMP max query response time: 10 seconds Last member query response interval: 1000 ms IGMP activity: 1 joins, 0 leaves Multicast routing on this interface: enabled Multicast TTL threshold: 0 Multicast designated router (DR): 1922.168.12.1 (this system) IGMP Querier: 129.168.12.1 (this system) Robustness: 2 Require-router-alert: no Last-member-query-interval: 30 deciseconds Startup-query-interval: 300 deciseconds Startup-query-count: 2 General-query-timer-expiry: 00:00:20 (hours:minutes: seconds) Startup-query-timer-expiry: off Other-querier-present-timer-expiry: off Multicast groups joined (number of users): 224.0.0.2(1) 224.2.2.2(1)

Example 2

In the following example, a query is issued for interface eth1 only. The reply indicates that IGMP is running on this interface, and it has two groups joined.

# show ip igmp interface eth1

eth1 is up Internet address: 192.168.11.1/24 IGMP on this interface: enabled Current IGMP router version: 2 IGMP query interval: 60 seconds IGMP max query response time: 10 seconds Last member query response interval 1000 ms IGMP activity: 1 joins, 0 leaves Multicast routing on this interface: enabled Multicast TTL threshold: 0 Multicast designated router (DR): 192.168.11.1 (this system) IGMP Querier: 192.168.11.1 Robustness: 2 Require-router-alert: no Last-member-query-interval: 30 deciseconds Startup-query-interval: 300 deciseconds Startup-query-count: 2 General-query-timer-expiry: 00:00:20 (hours:minutes: seconds) Startup-query-timer-expiry: off

show ip igmp interface

Internet Group Management Protocol (IGMP) Page 357

Other-querier-present-timer-expiry: off Multicast groups joined (number of users) 224.0.0.2(1) 224.1.1.1(1)

Example 3

In the following example, a query is issued for interface eth2 only. The reply indicates that IGMP is not running on the router.

# show ip igmp interface eth2

IGMP is not running

Field Descriptions

The following table describes the fields that appear in the IGMP Interface Information Query.

Table 21-1 IGMP Interface Information Query Fields

Field Description

Ethernet0/1 is up, line protocol is up

Interface type, number, and status

Internet address The IPv4 address of the interface

IGMP is enabled on interface Shows whether IGMP is enabled on an interface

Current IGMP router version IGMP router version

IGMP query interval Query interval in seconds

IGMP robustness Robustness value

IGMP max query response interval Query Response Interval in seconds

Last member query response interval

Last Member Query Response Interval in milliseconds

IGMP activity: joins, leaves Activity statistics showing the number of joins and leaves

Multicast routing on this interface Indicates whether multicast routing is enabled

Multicast TTL threshold The packet time-to-live threshold

Multicast designated router (DR) IPv4 address of the Designated Router

IGMP Querier IPv4 address of the Querier

Robustness Robustness value

Require-router-alert Indicates whether the require-router-alert option is on

Last-member-query-interval Last Member Query interval in deciseconds

show ip igmp interface-summary

Internet Group Management Protocol (IGMP) Page 358

Field Description

Startup-query-interval Startup Query Interval in deciseconds

Startup-query-count Number of General Queries to send during startup

General-query-timer-expiry The length of time, in hours, minutes, and seconds, until another General Query is sent

Startup-query-timer-expiry The length of time, in hours, minutes, and seconds, until another General Query is sent during startup

Other-querier-present-timer-expiry The length of time, in hours, minutes, and seconds, until the Other Querier Present Timer expires

Multicast groups joined (number of users)

Group address and number of hosts that joined the group

show ip igmp interface-summary

Name

show ip igmp interface-summary - displays simple summary information pertaining to IGMP interfaces

Syntax

show ip igmp interface-summary

Mode

User Execution

Parameters

none

Description

The show ip igmp interface-summary command displays the number of interfaces on which IGMP is

running.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example issues an interface summary query. The response indicates that

IGMP is running on five interfaces.

# show ip igmp interface-summary

show ip igmp static-groups

Internet Group Management Protocol (IGMP) Page 359

Number of active interfaces: 5

Example 2

The following example issues an interface summary query on a router on which IGMP is not running.

# show ip igmp interface-summary

IGMP is not running

show ip igmp static-groups

Name

show ip igmp static-groups - displays IGMP information regarding multicast static-group state

Syntax

show ip igmp static-groups

Mode

User Execution

Parameters

none

Description

The show ip igmp static-groups query displays information about all configured IGMP multicast static

groups.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays information pertaining to IGMP for all groups on all interfaces.

> show ip igmp static-groups

IGMP CONNECTED Static-Group Membership Group Address Interface Expires Last Reporter 224.1.1.1 fxp1 never 0.0.0.0 224.1.1.1 fxp0 never 0.0.0.0 224.1.1.2 fxp0 never 0.0.0.0 224.1.1.3 fxp1 never 0.0.0.0

Page 360

Chapter 17

Protocol Independent Multicast (PIM)

In This Chapter

Protocol Independent Multicast (PIM) Overview 360

ip pim assert-holdtime 361

ip pim dr-priority 362

ip pim hello-holdtime 363

ip pim hello-interval 363

ip pim jp-holdtime 364

ip pim jp-interval 365

ip pim lan-delay 366

ip pim mrt-interval 367

ip pim mrt-stale-multiplier 367

ip pim override-interval 368

ip pim triggered-hello-delay 369

show ip pim control-counters 370

show ip pim interface 371

show ip pim neighbor 373

Protocol Independent Multicast - Dense Mode (PIM-DM) 375

Protocol Independent Multicast - Sparse Mode (PIM-SM) 389

Protocol Independent Multicast (PIM) Overview

Traditional multicast routing mechanisms (for example, DVMRP and MOSPF) were intended for use within regions where groups are densely populated or bandwidth is universally plentiful. When groups, and senders to these groups, are distributed sparsely across a wide area, these "dense mode" schemes do not perform efficiently. PIM is made of two protocols, one for each type of group distribution. PIM Sparse Mode, PIM-SM, provides efficient routing for a group distributed sparsely across a wide area. PIM Dense Mode, PIM-DM, provides multicast routing for a densely populated group.

Multicasting protocols require two different functions in order to create source-based trees or group-based trees:

a set of routes used to calculate the reverse path forwarding

a mechanism by which to build trees

PIM is protocol independent because it depends on existing unicast routes to calculate the reverse path forwarding. In contrast, DVMRP passes this set of routes within the protocol.

There are two versions of the PIM-SM protocol. PIM-SM version 1 is documented in RFC 2117. PIM-SM version 2 was constructed to address some of the shortcomings of PIM-SM version 1. Advanced Routing Suite implements only version 2, which is an RFC but is not considered complete enough to implement (RFC 2362). In going from draft-ietf-pim-sm-v2-new-01 to draft-ietf-pim-sm-v2-new-02, the BSR functionality was removed and placed in its own internet draft. Advanced Routing Suite implements the PIM-SM protocol as described in draft-ietf-pim-sm-v2-new-02, but the BSR functionality as described in draft-ietf-pim-sm-v2-new-01.

ip pim assert-holdtime

Protocol Independent Multicast (PIM) Page 361

Note: PIM uses routes in the multicast Routing Information Base (RIB) to perform its RPF check. By default none of the IGPs (IS-IS, OSPF, RIP) place routes into the multicast RIB. They must be configured to do so. Check the relevant protocol's configuration section in order to obtain the correct syntax.

ip pim assert-holdtime

Name

ip pim assert-holdtime - specifies the number of seconds that Assert state should be maintained in

the absence of a refreshing Assert message

Syntax

ip pim assert-holdtime time-seconds

no ip pim assert-holdtime time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - specifies a time, in seconds, between 1 and 1,073,741,823, inclusive

Description

When a PIM router receives an Assert message, it modifies the outgoing interface list for a (*,G) or (S,G)

entry, as specified by the message. The lifetime of this modification is specified by the ip pim

assert-holdtime command. If another Assert message does not refresh the Assert state before the

lifetime expires, then the outgoing interface list reverts to its previous state.

The negative of this command, no ip pim assert-holdtime, removes the configured value and returns

this command to its default value. Note: Specifying a value for time-seconds in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If ip pim assert-holdtime is not specified, it is the same as if the user had specified the following:

(config-if)# ip pim assert-holdtime 180 or (config)# ip pim assert-holdtime 180

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a global assert-holdtime value of 100. For interface eth1, this value is overridden to be 140.

(config)# ip pim assert-holdtime 100

(config)# interface eth1

(config-if)# ip pim assert-holdtime 140

Example 2

The following example uses the negative form of the assert-holdtime command both globally and for interface eth1 to return the value to 180 seconds.

ip pim dr-priority

Protocol Independent Multicast (PIM) Page 362

(config)# no ip pim assert-holdtime

(config)# interface eth1

(config-if)# no ip pim assert-holdtime

ip pim dr-priority

Name

ip pim dr-priority - sets the priority for determining the designated router (DR)

Syntax

ip pim dr-priority level

no ip pim dr-priority level?

Mode

Global Configuration

Interface Configuration

Parameters

level - an integer between 1 and 4,294,967,295, inclusive

Description

PIM Hello messages can contain a priority field that is used to elect a designated router (DR) on a shared network. All Hello messages originated by Advanced Routing Suite contain such a priority. DRs are responsible for encapsulating multicast data from local sources into PIM-SM register messages and for unicasting them to the Rendezvous Point. The router with the highest priority wins the DR election. In the case of a tie, the router with the highest IP address wins.

If at least one neighbor on the network does not use Hello priorities, then election of a DR is carried out using only IP addresses, where the highest address wins.

The negative form of this command, no ip pim dr-priority, removes the configured priority and returns

it to its default value of 1. Note: Specifying a value for level in the no form of this command has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If ip pim dr-priority is not specified, it is the same as if the user had specified the following:

(config-if)# ip pim dr-priority 1 or (config)# ip pim dr-priority 1

Command History

NGC 2.2 - This command was introduced.

NGC 2.3 - The lower limit of this command was changed from 1 to 0.

Examples

The following example configures a default dr-priority of 4. This value is then overridden on interface 192.168.22.1 to be 3.

(config)# ip pim dr-priority 4

(config)# interface 192.168.22.1

(config-if)# ip pim dr-priority 3

ip pim hello-holdtime

Protocol Independent Multicast (PIM) Page 363

ip pim hello-holdtime

Name

ip pim hello-holdtime - specifies how long neighbors should wait for Hello messages before expiring

the sender's neighbor state

Syntax

ip pim hello-holdtime time-seconds

no ip pim hello-holdtime time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - specifies a time in seconds between 1 and 65535, inclusive

Description

PIM Hello messages contain a holdtime specifying how long neighbors must wait for Hello messages before

expiring the sender's neighbor state. The ip pim hello-holdtime command specifies the holdtime, in

seconds, to advertise in Hello messages.

The negative of this command, no ip pim hello-holdtime, removes the configured setting and returns

this value to the default of 105 seconds. Note: Specifying a value for time-seconds in the no form has no

effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim hello-holdtime is not specified, it is the same as if the user had specified the following:

(config)# ip pim hello-holdtime 105 or (config-if)# ip pim hello-holdtime 105

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the global hello holdtime to be 100 seconds and the holdtime for interface eth1 to be 140 seconds.

(config)# ip pim hello-holdtime 100

(config)# interface eth1

(config-if)# ip pim hello-interval

ip pim hello-interval

Name

ip pim hello-interval - specifies the frequency with which Hello messages are sent

Syntax

ip pim hello-interval time-seconds

ip pim jp-holdtime

Protocol Independent Multicast (PIM) Page 364

no ip pim hello-interval time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - specifies a time, in seconds, between 1 and 65535, inclusive

Description

PIM routers periodically multicast Hello messages on each network to which they are connected to alert

other routers to the presence of the sender. The ip pim hello-interval command specifies the time, in

seconds, between successive Hello messages.

The negative of this command, no ip pim hello-interval, removes the configured setting and returns

this value to the default of 30 seconds. Note: Specifying a value for time-seconds in the no form has no

effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim hello-interval is not specified, it is the same as if the user had specified the following:

(config)# ip pim hello-interval 30 or (config-if)# ip pim hello-interval 30

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the global hello-interval to be 100 seconds. This value is overridden to be 140 seconds on interface eth1.

(config)# ip pim hello-interval 100

(config)# interface eth1

(config-if)# ip pim hello-interval 140

ip pim jp-holdtime

Name

ip pim jp-holdtime - specifies the holdtime that is advertised on PIM Join/Prune messages

Syntax

ip pim jp-holdtime time-seconds

no ip pim jp-holdtime time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - specifies a time in seconds between 1 and 65535, inclusive

ip pim jp-interval

Protocol Independent Multicast (PIM) Page 365

Description

The ip pim jp-holdtime command specifies the holdtime that is advertised in PIM Join/Prune messages.

Receivers must wait at least this long after receiving a Join/Prune message before deleting the Join/Prune state associated with the advertiser. The recommend value is 3.5 * jp-interval.

The negative form of this command, no ip pim jp-holdtime, removes the configured value and returns

this to its default value of 210 seconds. Note: Specifying a value for time-seconds in the no form has no

effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim jp-holdtime is not specified, it is the same as if the user had specified the following:

(config)# ip pim jp-holdtime 210 or (config-if)# ip pim jp-holdtime 210

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the default jp-holdtime to be 100 seconds and the jp-holdtime on interface eth1 to be 140 seconds.

(config)# ip pim jp-holdtime 100

(config)# interface eth1

(config-if)# ip pim jp-holdtime 140

ip pim jp-interval

Name

ip pim jp-interval - specifies the number of seconds between successive Join/Prune messages sent

to upstream neighbors

Syntax

ip pim jp-interval time-seconds

no ip pim jp-interval time-seconds?

Mode

Global Configuration

Interface Configuration

Parameters

time-seconds - specifies a time in seconds between 1 and 65535, inclusive

Description

The Join/Prune state on an upstream neighbor must be refreshed by periodic Join/Prune messages. The ip

pim jp-interval command specifies the number of seconds between successive Join/Prune messages

sent to upstream neighbors to maintain the neighbor’s Join/Prune state.

The negative form of this command, no ip pim jp-interval, removes the configured value and returns

the value to its default. Note: Specifying a value for time-seconds in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

ip pim lan-delay

Protocol Independent Multicast (PIM) Page 366

Default

If ip pim jp-interval is not specified, it is the same as if the user had specified the following:

(config)# ip pim jp-interval 60 or (config-if)# ip pim jp-interval 60

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the default jp-interval to be 100 seconds and the jp-interval on interface eth1 to be 140 seconds.

(config)# ip pim jp-interval 100

(config)# interface eth1

(config-if)# ip pim jp-interval 100

ip pim lan-delay

Name

ip pim lan-delay - specifies the value to advertise as the LAN Delay value in the Lan Prune Delay

option in PIM Hello messages

Syntax

ip pim lan-delay time-milliseconds

no ip pim lan-delay time-milliseconds?

Mode

Interface Configuration

Parameters

time-milliseconds - an integer between 1 and 65535, specifying a number of seconds

Description

Use the ip pim lan-delay command to configure the value to advertise as the LAN Delay value in the

Lan Prune Delay option in PIM Hello messages. This value is used to tune the value of the J/P Override interval. It is configured in units of milliseconds.

The negative form of this command, no ip pim lan-delay, removes the configured time-milliseconds

value and returns this to its default value of 500 milliseconds. Note: Specifying a value for time-milliseconds

in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim lan-delay is not specified, it is the same as if the user had specified the following:

(config-if)# ip pim lan-delay 500

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the Lan Delay for interface eth1 to be 700.

ip pim mrt-interval

Protocol Independent Multicast (PIM) Page 367

(config)# interface eth1

(config-if)# ip pim lan-delay 700

(config-if)# exit

ip pim mrt-interval

Name

ip pim mrt-interval - specifies the number of seconds to wait between examinations of a PIM

component's multicast routing table (MRT)

Syntax

ip pim mrt-interval time-seconds

no ip pim mrt-interval time-seconds?

Mode

Global Configuration

Parameters

time-seconds - an integer between 1 and 3600, inclusive, specifying a number of seconds

Description

A PIM component's MRT is examined periodically in order to remove entries that have been marked for

deletion. The ip pim mrt-interval command specifies the number of seconds to wait between

examinations. This can be a computationally expensive operation if the number of entries is large.

The negative form of this command, no ip mrt-interval, removes the configured time-seconds value

and returns this to its default value of 15 seconds. Note: Specifying a value for time-seconds in the no form

has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim mrt-interval is not specified, it is the same as if the user had specified the following:

(config)# ip pim mrt-interval 15

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the MRT interval to be 100 seconds.

(config)# ip pim mrt-interval 100

(config)#

ip pim mrt-stale-multiplier

Name

ip pim mrt-stale-multiplier - together with the ip pim mrt-interval command, specifies the

minimum number of seconds that a source can be silent before its corresponding (S,G) entry can be timed out

ip pim override-interval

Protocol Independent Multicast (PIM) Page 368

Syntax

ip pim mrt-stale-multiplier multiplier

no ip pim mrt-stale-multiplier multiplier?

Mode

Global Configuration

Parameters

multiplier - an unsigned integer between 1 and 100, inclusive

Description

When a source stops sending to a group, the corresponding (S,G) entry is said to have become "stale" and becomes a candidate for deletion from the PIM multicast forwarding table (MRT). The PIM-SM protocol defines a Keep-Alive Timer (KAT) for each (S,G) entry, which is reset by the arrival of data from source S addressed to group G. If the KAT ever expires, and if other conditions are met, then the entry can be

deleted. The ip pim mrt-stale-multiplier command, together with the ip pim mrt-interval

command, specifies the minimum number of seconds that a source must be silent before the entry is

considered stale. The value, multiplier, specified in the ip pim mrt-stale-multiplier command

indicates that a source must be silent for m * ip pim mrt-interval in order to be declared stale.

The negative form of this command, no ip pim mrt-stale-multiplier, removes the configured

multiplier value and returns this to its default value of 14 intervals. Note: Specifying a value for multiplier in

the no form has no effect on the configuration. Thus, it is displayed above as optional.

Defaults

If ip pim mrt-stale-multiplier is not specified, it is the same as if the user had specified the

following:

(config)# ip pim mrt-stale-multiplier 14

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the MRT stale multiplier value to be 10 seconds.

(config)# ip pim mrt-stale-multiplier 10

(config)#

ip pim override-interval

Name

ip pim override-interval - specifies the value to advertise as the Override Interval in the Lan Prune

Delay option of PIM Hello messages

Syntax

ip pim override-interval time-milliseconds

no ip pim override-interval time-milliseconds?

Mode

Interface Configuration

ip pim triggered-hello-delay

Protocol Independent Multicast (PIM) Page 369

Parameters

time-milliseconds - an integer between 1 and 65535, specifying a number of seconds

Description

Use the ip pim override-interval command to configure the value to advertise as the Override

Interval value in the Lan Prune Delay option in PIM Hello messages. This value is used to tune the value of the J/P Override interval. It is configured in units of milliseconds.

The negative form of this command, no ip pim override-interval, removes the configured

time-milliseconds value and returns this to its default value of 2500 milliseconds. Note: Specifying a value

for time-milliseconds in the no form has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If ip pim override-interval is not specified, it is the same as if the user had specified the following:

(config-if)# ip pim override-interval 2500

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the Lan Delay for interface eth1 to be 2900 milliseconds.

(config)# interface eth1

(config-if)# ip pim override-interval 2900

(config-if)# exit

ip pim triggered-hello-delay

Name

ip pim triggered-hello-delay - specifies the number of seconds to delay between triggered Hello

messages

Syntax

ip pim triggered-hello-delay time-seconds

no ip pim triggered-hello-delay time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - an integer from 1 to 65535, inclusive

Description

The ip pim triggered-hello-delay command configures the maximum delay for a triggered Hello

message. The negative form of this command, no ip pim triggered-hello-delay, removes the

configured time-seconds value and returns this to its default value of 5 seconds. Note: Specifying a value

for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim triggered-hello-delay is not specified, it is the same as if the user had specified the

following:

show ip pim control-counters

Protocol Independent Multicast (PIM) Page 370

(config-if)# ip pim triggered-hello-delay 5

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the Triggered Hello delay to be 10 seconds on interface fxp3.

(config)# interface fxp3

(config-if)# ip pim triggered-hello-delay 10

(config-if)# exit

(config)#

show ip pim control-counters

Name

show ip pim control-counters - displays counts for both sent and received PIM control packets

Syntax

show ip pim control-counters

Mode

User Execution

Parameters

none

Description

The show ip pim control-counters query displays counts for both sent and received PIM control

packets on all interfaces.

Command History

NGC 2.2 - This command was introduced.

Examples

The following is a request to return information about all PIM packets.

> show ip pim control-counters

PIM Control Counters Received Sent Invalid Assert 10 5 0 Graft 20 37 2 Graft Ack 25 20 1 Hello 1232 453 0 Joins 5 10 20 Prunes 10 20 1 State Refresh 8 7 1

Field Descriptions

The following table describes the fields that appear in the PIM Control Packet Counters Query.

Table 22-1 PIM Control Packet Counters Query Fields

show ip pim interface

Protocol Independent Multicast (PIM) Page 371

Field Description

Received Number of packets of the given type that have been received

Sent Number of packets of the given type that have been sent

Invalid Number of packets of the given type that were received but were invalid

show ip pim interface

Name

show ip pim interface - displays information about the interfaces on which PIM is running

Syntax

show ip pim interface [ipv4_addr | name]? detail?

Mode

User Execution

Parameters

ipv4_addr | name - optionally specify either an IPv4 address or a physical interface name

detail - displays IGMPv3 style group information and source information. Specifying this is optional.

Description

Use show ip pim interface to obtain information about a specific interface or all interfaces on which PIM

is running.

This query has two forms. If the query is issued without arguments, then information on about all interfaces over which PIM is running is returned. Alternatively, the query can be issued with a specific interface. If this is the case, then the reply will contain information pertaining only to that referenced interface.

Note that if interfaces are added to the set of interfaces over which PIM is running after this query has been issued but before the query is finished, it is not guaranteed that the new interfaces will be reported. Similarly, if PIM is de-configured on an interface after the query has been issued but before the query is finished, then the interface may or may not be reported.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example displays interface information for all interfaces on which PIM is running.

> show ip pim interface

Address Interface Mode Neighbor Hello DR Count Interval

show ip pim interface

Protocol Independent Multicast (PIM) Page 372

192.168.10.1 fxp0 Dense 5 30 192.168.10.1 10.1.57.28 ex0 Sparse 2 50 10.1.57.30

Example 2

The following example displays detailed interface information for interface fxp0.

> show ip pim interface fxp0 detail

fxp0 is up, line protocol is up Internet address is 192.168.10.1/25 Multicast packets in/out: 0/0 Multicast boundary: not set Multicast TTL threshold: 1 PIM: enabled PIM version:2, mode: dense PIM DR: 192.168.10.1 (this system) PIM Neighbor Count: 5 PIM Hello/Query Interval: 30 seconds PIM State-Refresh processing: enabled PIM State-Refresh origination: enabled, interval 60 seconds PIM domain border: disabled

Field Descriptions

The following table describes the fields that appear in the PIM Interface Information Query.

Table 22-1 PIM Interface Information Query Fields

Field Description

Address Shows the IP address used by PIM on the interface

Interface The physical interface name

Mode The PIM mode active on the interface

Neighbor Count Number of PIM neighbors reached through the interface

Hello Interval The number of seconds at which hello packets are sent

DR The IP address of the elected designated router on the interface

<interface-name> (for example, fxp0)

The physical name of the interface and the administrative state of it (up or down)

line protocol Carrier status of interface (up or down)

Internet address The IPv4 address used by PIM on the interface

show ip pim neighbor

Protocol Independent Multicast (PIM) Page 373

Field Description

Multicast packets The number of multicast packets received from/forwarded out of this interface

Multicast boundary Indicates whether any administratively scoped boundaries are set on the interface

Multicast TTL The time-to-live threshold used on the interface

PIM Indicates whether PIM is enabled or disabled

PIM version Indicates the PIM version configured on the interface

mode Indicates whether PIM dense or sparse mode is configured on the interface

PIM DR The IPv4 address of the elected designated router on the interface

PIM Neighbor Count The number of PIM neighbors reached through this interface

PIM Hello/Query Interval The PIM hello interval configured on the interface

PIM State-Refresh processing Indicates whether the processing of PIM state refresh messages is enabled or disabled on the interface

PIM State-Refresh origination Indicates whether the origination of PIM state refresh messages is enabled or disabled on the interface

interval The number of seconds between PIM state refresh messages

PIM domain border Indicates whether the interface is a PIM domain border

show ip pim neighbor

Name

show ip pim neighbor - displays information about a router’s PIM neighbors

Syntax

show ip pim neighbor name?

show ip pim neighbor

Protocol Independent Multicast (PIM) Page 374

Mode

User Execution

Parameters

name - optionally specify an interface name

Description

The show ip pim neighbor query displays information about a router’s PIM neighbors on all interfaces or

on a specific interface.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example displays information about all of this router’s PIM neighbors.

> show ip pim neighbor

PIM Neighbor Table Neighbor Address Interface Uptime Expires Mode 192.168.10.1 fxp0 10:23:43 00:01:10 Dense 192.168.10.2 fxp0 10:23:43 00:01:10 Dense (DR) 192.168.10.3 fxp0 10:23:43 00:01:10 Dense 192.168.10.4 fxp0 10:23:43 00:01:10 Dense 10.0.0.10 ex0 00:00:20 00:01:25 Sparse 10.0.0.20 ex0 00:00:20 00:01:25 Sparse 10.0.0.21 ex0 00:00:20 00:01:25 Sparse (DR) 10.0.0.22 ex0 00:00:20 00:01:25 Sparse

Example 2

The following example displays information about this router’s PIM neighbors on interface fxp0.

> show ip pim neighbor fxp0

PIM Neighbor Table Neighbor Address Interface Uptime Expires Mode 192.168.10.1 fxp0 10:23:43 00:01:10 Dense 192.168.10.2 fxp0 10:23:43 00:01:10 Dense (DR) 192.168.10.3 fxp0 10:23:43 00:01:10 Dense 192.168.10.4 fxp0 10:23:43 00:01:10 Dense

Page 375

Chapter 18

Protocol Independent Multicast - Dense Mode (PIM-DM)

In This Chapter

Protocol Independent Multicast - Dense Mode (PIM-DM) Overview 375

ip pim dense-mode 375

ip pim graft-retry-interval 376

ip pim require-genid 377

ip pim source-lifetime 378

ip pim state-refresh-capable 378

ip pim state-refresh-interval 379

ip pim state-refresh-rate-limit 380

ip pim state-refresh-ttl 381

ip pim dense trace file 381

ip pim dense trace flag 382

show ip pim dense-mode interface-summary 384

show ip pim dense-mode mrt 384

show ip pim dense-mode mrt-summary 386

show ip pim grafts 387

Protocol Independent Multicast - Dense Mode (PIM-DM) Overview

The PIM-DM protocol can be considered the follow-on to the DVMRP protocol. It is a "flood-and-prune" protocol. Multicast data from a source addressed to a multicast group is "flooded" to all parts of the network. Last-hop routers that detect no member of the destination group "prune" back towards the source. This type of multicast tends to be more efficient when receivers are "densely" distributed throughout the network.

The biggest difference between PIM-DM and DVMRP is that PIM-DM is only a multicast tree-building protocol whereas DVMRP is both a tree-building protocol and a network topology protocol. PIM-DM requires a unicast protocol such as OSPF to be running in the network in order to establish the underlying unicast topology.

PIM-DM namely differs from PIM-SM in that PIM-SM is an "explicit-join" protocol. An "explicit-join" grows branches of the multicast distribution trees from receivers back towards the root of the tree. In this way, multicast traffic only ever flows to members of the group. PIM-DM also differs from PIM-SM in that in PIM-DM all distribution trees are rooted at the sender. PIM-DM has no notion of shared trees, Rendezvous-Points (RPs), (*,G) state, and so on.

Note: PIM uses routes in the multicast Routing Information Base (RIB) to perform its RPF check. By default none of the IGPs (OSPF, RIP) place routes into the multicast RIB. They must be configured to do so. Check the relevant protocol's configuration section in order to obtain the correct syntax.

ip pim dense-mode

Name

ip pim dense-mode - enables PIM dense mode on an interface

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 376

Syntax

ip pim dense-mode

no ip pim dense-mode

Mode

Interface Configuration

Parameters

none

Description

The ip pim dense-mode command enables PIM dense mode on the associated interface.

Default

PIM dense mode is disabled by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the PIM dense mode protocol on interface fxp0.

(config)# interface fxp0

(config-if)# ip pim dense-mode

ip pim graft-retry-interval

Name

ip pim graft-retry-interval - specifies the value to use for the Retry Interval for sending Graft

messages if a Graft acknowledgement has not been received

Syntax

ip pim graft-retry-interval time-seconds

no ip pim graft-retry-interval time-seconds?

Mode

Interface Configuration

Parameters

time-seconds - specifies an integer between 1 and 65535, inclusive, for the number of seconds

Description

The ip pim graft-retry-interval command specifies the value to use for the Retry Interval for

sending Graft messages if a Graft Acknowledgement has not been received. The negative form of this

command, no ip pim graft-retry-interval, removes the configured time-seconds value and returns

it to its default. Note: Specifying a value for time-seconds in the no form has not effect on the configuration.

Thus, it is displayed above as optional.

Default

If ip pim graft-retry-interval is not specified, it is the same as if the user had specified the

following:

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 377

(config-if)# ip pim graft-retry-interval 3

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a graft retry interval of 10 seconds for interface fxp0.

(config)# interface fxp0

(config-if)# ip pim dense mode

(config-if)# ip pim graft-retry-interval 10

(config-if)# exit

ip pim require-genid

Name

ip pim require-genid - specifies whether to reject packets without a generation ID

Syntax

ip pim require-genid

no ip pim require-genid

Mode

Interface Configuration

Parameters

none

Description

Use the ip pim require-genid command to specify that Advanced Routing Suite should reject packets

without the generation ID hello option. The negative form of this command, no ip pim require-genid,

specifies that Advanced Routing Suite will allow such packets.

Default

Advanced Routing Suite accepts packets without a generation ID by default. Therefore, if ip pim

require-genid is not specified, it is the same as if the user had specified the following:

(config-if)# no ip pim require-genid

Command History

NGC 2.2 - This command was introduced.

Example

The following example specifies that Advanced Routing Suite should reject packets that do not have a generation ID.

(config)# interface fxp1

(config-if)# ip pim dense-mode

(config-if)# ip pim require-genid

(config-if)# exit

(config)#

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 378

ip pim source-lifetime

Name

ip pim source-lifetime - specifies the interval during which a directly attached router will continue to

send State Refresh messages in the absence of additional multicast data

Syntax

ip pim source-lifetime time-seconds

no ip pim source-lifetime time-seconds?

Mode

Global Configuration

Parameters

time-seconds - the time in seconds, specified as a non-negative integer between 4 and 32766, inclusive

Description

The ip pim source-lifetime command specifies the interval during which a directly attached router will

continue to send State Refresh messages in the absence of additional multicast data.

The negative form of this command, no ip pim source-lifetime, removes the configured value and

returns this to its default value of 210 seconds. Note: Specifying a value for time-seconds in the no form of

this command has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim source-lifetime is not specified, it is the same as if the user had specified the following:

(config)# ip pim source-lifetime 210

Command History

NGC 2.2 - This command was introduced.

NGC 2.3 - The lower limit of this command changed from 1 to 4.

Examples

The following example configures a source lifetime of 150 seconds.

(config)# ip pim source-lifetime 150

ip pim state-refresh-capable

Name

ip pim state-refresh-capable - specifies whether to enable the PIM-DM State Refresh option

Syntax

ip pim state-refresh-capable

no ip pim state-refresh-capable

Mode

Interface Configuration

Parameters

none

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 379

Description

The ip pim state-refresh-capable command specifies whether to enable the PIM-DM State Refresh

option. Use this command to optimize network traffic by reducing the amount of flooding and pruning that occurs.

Default

The state refresh capability is enabled by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example disables the state refresh capability on interface eth3.

(config)# interface eth3

(config-if)# ip pim dense-mode

(config-if)# no ip pim state-refresh-capable

(config-if)# exit

(config)#

Example 2

The following example re-enables the state refresh capability on interface eth3. Note that dense mode was already configured on interface eth3 in Example 1.

(config)# interface eth3

(config-if)# ip pim state-refresh-capable

(config-if)# exit

(config)#

ip pim state-refresh-interval

Name

ip pim state-refresh-interval - specifies the number of seconds between sent State Refresh

messages

Syntax

ip pim state-refresh-interval time-seconds

no ip pim state-refresh-interval time-seconds?

Mode

Global Configuration

Parameters

time-seconds - the time in seconds, specified as a non-negative integer between 1 and 255, inclusive

Description

The ip pim state-refresh-interval command specifies the frequency for sending State Refresh

messages. The negative form of this command, no ip pim state-refresh-interval, removes the

configured value and returns this to its default value of 60 seconds. Note: Specifying a value for

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 380

time-seconds in the no form of this command has no effect on the configuration. Thus, it is displayed above

as optional.

Default

If ip pim state-refresh-interval is not specified, it is the same as if the user had specified the

following:

(config)# ip pim state-refresh-interval 60

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the state refresh interval to be 70 seconds.

(config)# ip pim state-refresh-interval 70

ip pim state-refresh-rate-limit

Name

ip pim state-refresh-rate-limit - configures the minimum number of seconds that must pass

before a source-group combination will accept another State Refresh message

Syntax

ip pim state-refresh-rate-limit time-seconds

no ip pim state-refresh-rate-limit time-seconds?

Mode

Global Configuration

Parameters

time-seconds - an integer between 0 and 254, inclusive, specifying a number of seconds

Description

Use the ip pim state-refresh-rate-limit command to specify the minimum length of time that must

pass before another State Refresh message will be accepted for a particular source-group combination. The

negative form of this command, no ip pim state-refresh-rate-limit, removes the configured

time-seconds value and returns this to its default value of 30 seconds. Note: Specifying a value for

time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim state-refresh-rate-limit is not specified, it is the same as if the user had specified the

following:

(config)# ip pim state-refresh-rate-limit 30

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the state refresh rate limit value to be 45 seconds.

(config)# ip pim state-refresh-rate-limit 45

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 381

ip pim state-refresh-ttl

Name

ip pim state-refresh-ttl - configures the TTL value that will be used in state refresh messages

originated by this router

Syntax

ip pim state-refresh-ttl num

no ip pim state-refresh-ttl num?

Mode

Global Configuration

Parameters

num - an integer from 1 to 255, inclusive

Description

Use the ip pim state-refresh-ttl command to configure the Time-To-Live (TTL) value that will be

used in state refresh messages originated by this router. The negative form of this command, no ip pim

state-refresh-ttl, removes the configured num value and returns this to its default value of 255. Note:

Specifying a value for num in the no form has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If ip pim state-refresh-ttl is not specified, it is the same as if the user had specified the following:

(config)# ip pim state-refresh-ttl 255

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the state refresh TTL to be 100.

(config)# ip pim state-refresh-ttl 100

ip pim dense trace file

Name

ip pim dense trace file - specifies the file to receive tracing information, the size of the file, whether

to overwrite existing files, and the maximum number of files allowed

Syntax

ip pim dense trace file file_name [no-timestamp || overwrite]?

no ip pim dense trace file file_name [no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 382

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. The ip pim dense trace file command specifies a file for tracing

of all PIM-DM events. The negative form of this command disables this tracing. The specific events that are

traced are controlled by the ip pim dense trace flag command.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config)# ip pim dense trace file /var/log/pimdm.log no-timestamp

(config)# ip pim dense trace file /var/log/pimdm.log

The option given in the second command completely replaces that given in the first.

Default

PIM-DM tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, PIM-DM tracing is written to the file "/var/tmp/pimdm.log". No timestamp will display at the beginning of the trace lines.

(config)# ip pim dense trace file /var/tmp/pimdm.log no-timestamp

ip pim dense trace flag

Name

ip pim dense trace flag - specifies PIM-DM-specific tracing options as well as options that are

common across all protocols

Syntax

ip pim dense trace flag ( [ route | normal | state | policy | task | timer | all | alert | debug ] ) | ( [ assert | graft | hello | packets | state-refresh ] [ send | receive | send-receive ]? [detail?] )

no ip pim dense trace flag ( [ route | normal | state | policy | task | timer | all | alert | debug ] ) | ( [ assert | graft | hello | packets | state-refresh ] [ send | receive | send-receive ]? [detail?] )

Mode

Global Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 383

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or

exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

IM-specific flags that do not allow associated action items:

[ alert | debug ] - These PIM-DM-specific flags cannot be associated with the send, receive,

send-receive, or detail action items. These flags are defined as follows:

alert - trace certain failures, such as memory allocation failures, that result in a strong warning

debug - extra trace information of use mainly to developers

IM-specific flags that allow associated action items:

[ assert | graft | hello | packets | state-refresh ] - These PIM-DM-specific flags can be

associated with the send, receive, send-receive, and detail action items. These flags are defined as follows:

assert - specifies to trace PIM-DM Assert packets

graft - specifies to trace PIM-DM graft messages

hello - specifies to trace PIM-DM Hello packets

packets - specifies to trace PIM-DM packets

state-refresh - specifies to trace PIM-DM state-refresh messages

[ send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the ip pim dense trace flag command to specify tracing flags for PIM-DM tracing. Each flag must

reside on its own configuration line. For example, you cannot specify to trace both assert and graft packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received state-refresh and graft messages are traced in detail. This tracing information will be written to the file /var/tmp/pimdm.log.

(config)# ip pim dense trace file /var/tmp/pimdm.log

(config)# ip pim dense trace flag state-refresh send-receive detail

(config)# ip pim dense trace flag graft send-receive detail

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 384

show ip pim dense-mode interface-summary

Name

show ip pim dense-mode interface-summary - displays summarized information about interfaces

currently running PIM Dense Mode

Syntax

show ip pim dense-mode interface-summary

Mode

User Execution

Parameters

none

Description

The show ip pim dense-mode interface-summary query displays a summary of the number of

interfaces currently running PIM-DM.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays information returned in response to the Dense Mode Interface Summary query.

> show ip pim dense-mode interface-summary

PIM Dense Mode Interface Summary Number of active interfaces 100

Field Descriptions

The following table describes the fields that appear in the PIM-DM MRT Summary Query.

PIM-DM MRT Summary Query Fields

Field Description

Number of active interfaces The number of active interfaces in PIM Dense Mode

show ip pim dense-mode mrt

Name

show ip pim dense-mode mrt - displays detailed information about S,G entries

Syntax

show ip pim dense-mode mrt [ group group-prefix || source source-prefix ]?

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 385

Mode

User Execution

Parameters

group group-prefix - optionally specify a group prefix in the format a.b.c.d/e

source source-prefix - optionally specify a source prefix in the format a.b.c.d/e

Description

The show ip pim dense-mode mrt query displays detailed information about S,G entries in the Multicast

Routing Table.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example displays detailed MRT information for all S,G entries present.

> show ip pim dense-mode mrt

224.1.1.1 192.168.10.1 uptime 01:02:09 Incoming interface: fxp1, index 2, vif 1 Outgoing interface list: fxp2, index 3, vif 2 fxp3,index 4, vif 3

192.168.121.1 uptime 12:12:12 Incoming interface: fxp2, index 3, vif 2 Outgoing interface list: fxp1, index 2, vif 1

226.2.2.2 * uptime 02:03:24 Incoming interface: null Outgoing interface list: fxp2, index 3, vif 2

10.1.1.1 uptime 00:10:13 Incoming interface: fxp3, index 4, vif 3 Outgoing interface list: fxp2, index 3, vif 2

Example 2

The following query displays detailed MRT information for group prefix 226.0.0.0/24.

> show ip pim dense-mode mrt group 226.0.0.0/24

226.2.2.2 * uptime 02:03:24 Incoming interface: null Outgoing interface list: fxp2, index 3, vif 2

10.1.1.1 uptime 00:10:13 Incoming interface: fxp3, index 4, vif 3 Outing interface list: fxp2, index 3, vif 2

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 386

Example 3

The following query displays detailed MRT information for group prefix 226.0.0.0/24 with source prefix 10.0.0.0/8.

> show ip pim dense-mode mrt group 226.0.0.0/24 source 10.0.0.0/8

226.2.2.2 10.1.1.1 uptime 00:10:13 Incoming interface: fxp3, index 4, vif 3 Outgoing interface list: fxp2, index 3, vif 2

Field Descriptions

The following table describes the fields that appear in the PIM-DM MRT Detail Information Query (using fields in Example 3).

PIM-DM MRT Detail Information Query Fields

Field Description

226.2.2.2 Address of multicast group

10.1.1.1 IP address of source

uptime Amount of time the entry has existed

fxp3 The physical interface name

index The interface index

vif The interface vif number

show ip pim dense-mode mrt-summary

Name

show ip pim dense-mode mrt-summary - displays summarized information about the PIM-DM Multicast

Routing Table

Syntax

show ip pim dense-mode mrt-summary

Mode

User Execution

Parameters

none

Description

The show ip pim dense-mode mrt-summary query displays a summary of the number of S,G entries

present in the Multicast Routing Table.

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 387

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays information returned in response to the Dense Mode MRT Summary query.

> show ip pim dense-mode mrt-summary

PIM DM MRT Summary Number of S,G entries 100

Field Descriptions

The following table describes the fields that appear in the PIM-DM MRT Summary Query.

PIM-DM MRT Summary Query Fields

Field Description

Number of S,G entries The number of entries in the MRT

show ip pim grafts

Name

show ip pim grafts - displays information about unacknowledged grafts

Syntax

show ip pim grafts

Mode

User Execution

Parameters

none

Description

The show ip pim grafts query displays information about unacknowledged grafts.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example information displays as a result of the show ip pim grafts query.

> show ip pim grafts

PIM Graft Information 192.168.10.1, 224.1.1.1 age 00:00:24 retransmit in 00:00:02

Field Descriptions

The following table describes the fields that appear in the PIM-DM Graft Retransmission Query.

Protocol Independent Multicast - Dense Mode (PIM-DM)

Protocol Independent Multicast (PIM) Page 388

PIM-DM Graft Retransmission Query Fields

Field Description

192.168.10.1 Address of the source

224.1.1.1 Address of the group

age Amount of time that graft has been unacknowledged

retransmit in Time left until the next transmission of graft

Page 389

Chapter 19

Protocol Independent Multicast - Sparse Mode (PIM-SM)

In This Chapter

Protocol Independent Multicast - Sparse Mode (PIM-SM) Overview 390

ip pim associate-msdp 390

ip pim bsr-admin-scope 390

ip pim bsr-border 391

ip pim bsr-candidate 392

ip pim bsr-candidate global 393

ip pim bsr-candidate group 393

ip pim bsr-candidate interval 394

ip pim bsr-candidate priority 395

ip pim bsr-holdtime 396

ip pim dr-switch-immediate 396

ip pim mrt-spt-multiplier 397

ip pim probe-interval 398

ip pim register-suppression-timeout 399

ip pim rp-address 399

ip pim rp-candidate 400

ip pim rp-candidate advertisement-interval 401

ip pim rp-candidate group 402

ip pim rp-candidate holdtime 403

ip pim rp-candidate priority 403

ip pim rp-switch-immediate 404

ip pim sparse-mode 405

ip pim threshold 406

ip pim threshold-dr 407

ip pim threshold-rp 407

ip pim trace file 408

ip pim trace flag 410

ip pim whole-packet-checksum 411

show ip pim bsr-router 412

show ip pim cbsr 412

show ip pim rp 413

show ip pim rp-candidate 414

show ip pim rp-hash 414

show ip pim sparse-mode join-prune xmit 415

show ip pim sparse-mode mrt 415

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 390

Protocol Independent Multicast - Sparse Mode (PIM-SM) Overview

PIM-SM differs from PIM-DM in that PIM-SM is an "explicit-join" protocol. An "explicit-join" grows branches of the multicast distribution trees from receivers back towards the root of the tree. In this way, multicast traffic only ever flows to members of the group. PIM-SM also differs from PIM-DM in that in PIM-DM all distribution trees are rooted at the sender. PIM-DM has no notion of shared trees, Rendezvous-Points (RPs), (*,G) state, and so on.

You can configure PIM-SM by entering an ip pim sparse-mode command. This indicates that only

PIM-SM should run on the associated interfaces.

Note: PIM uses routes in the multicast Routing Information Base (RIB) to perform its RPF check. By default none of the IGPs (IS-IS, OSPF, RIP) place routes into the multicast RIB. They must be configured to do so. Check the relevant protocol's configuration section in order to obtain the correct syntax.

ip pim associate-msdp

Name

ip pim associate-msdp - informs the MSDP component of active sources in the local PIM-SM domain

Syntax

ip pim associate-msdp

no ip pim associate-msdp

Mode

Global Configuration

Parameters

none

Description

Use the ip pim associate-msdp command to inform the MSDP protocol of active sources in the local

PIM-SM domain. The negative form of this command, no ip pim associate-msdp, removes this

association with the MSDP protocol.

Default

If ip pim associate-msdp is not specified, it is the same as if the user had specified the following:

(config)# no ip pim associate-msdp

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the Associate MSDP option.

(config)# ip pim associate-msdp

ip pim bsr-admin-scope

Name

ip pim bsr-admin-scope - configures additional rules when using the BSR RP set distribution

mechanism

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 391

Syntax

ip pim bsr-admin-scope

no ip pim bsr-admin-scope

Mode

Global Configuration

Parameters

none

Description

This command specifies that the Admin Scope BSR rules, as defined in the IETF document draft-ietf-pim-sm-bsr-02, are to be used to distribute RP set information. By default, Advanced Routing Suite uses the single-BSR-per-domain BSR rules to distributed RP set information.

Note that it is a misconfiguration to combine these two styles of BSR in the same PIM-SM domain. If a BSR

mechanism is desired for distributing RP set information, then all routers must be configured with ip pim

bsr-admin-scope. If not, then none of them may be configured with ip pim bsr-admin-scope.

Furthermore, when reconfiguring a router from using the Admin Scope BSR rules to using the single-BSR-per-domain BSR rules, or vice versa, all BSR state on the router is reset, which can result in a disruption of multicast traffic.

Default

If ip pim bsr-admin-scope is not specified, it is the same as if the user had specified the following:

(config)# no ip pim bsr-admin-scope

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies to use Admin Scope BSR rules when using the BSR RP set distribution mechanism.

(config)# ip pim bsr-admin-scope

ip pim bsr-border

Name

ip pim bsr-border - configures a PIM boundary on the associated interface

Syntax

ip pim bsr-border

no ip pim bsr-border

Mode

Interface Configuration

Parameters

none

Description

The ip pim bsr-border command configures a PIM boundary on the associated interface. A PIM

boundary prevents the transmission and receipt of Bootstrap Router (BSR) messages. This option is useful

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 392

when joining two administratively separate multicast domains via Multicast Source Discover Protocol (MSDP).

The negative form of this command, no ip pim bsr-border, remove any existing PIM border configured

on the interface.

Default

If ip pim bsr-border is not specified, it is the same as if the user had specified the following:

(config-if)# no ip pim bsr-border

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the PIM sparse mode protocol on interface fxp1. A PIM border is also configured on this interface.

(config)# interface fxp1

(config-if)# ip pim sparse-mode

(config-if)# ip pim bsr-border

(config-if)# exit

(config)#

ip pim bsr-candidate

Name

ip pim bsr-candidate - configures a candidate bootstrap router on a specified interface

Syntax

ip pim bsr-candidate interface

no ip pim bsr-candidate interface?

Mode

Global Configuration

Parameters

interface - a physical interface name or a valid IPv4 address for the BSR message origination

Description

The ip pim bsr-candidate configures the router to be a Candidate Bootstrap Router (CBSR) on the

specified interface. Only one interface can be configured as a CBSR. If any of the BSR Candidate commands are given, then candidate BSR mechanism is enabled. If an interface is not specified, then the first PIM-SM enabled interface is selected.

The negative form of this command, no ip pim bsr-candidate, removes the configured interface. Note:

Specifying a value for interface in the no form has no effect on the configuration. It will not remove other

BSR candidate configurations, such as priority or interval. Thus, it is displayed above as optional.

Default

A router does not act as a CBSR by default.

Command History

NGC 2.2 - This command was introduced.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 393

Examples

The following example configures the router to be a CBSR on interface fxp0.

(config)# ip pim bsr-candidate fxp0

(config)#

ip pim bsr-candidate global

Name

ip pim bsr-candidate global - configures the router be a CBSR in the global scope range

Syntax

ip pim bsr-candidate global [priority level]?

no ip pim bsr-candidate global [priority level]?

Mode

Global Configuration

Parameters

priority level - optionally specify a priority to be associated with the router volunteering to be a

Candidate Bootstrap Router (CBSR) on the given interface. The value for level can be an integer from 0 to 255, inclusive.

Description

The ip pim bsr-candidate global command configures a router to be a CSBR in global scope range

for the new ASBSR implementation syntax (for group ranges not within 239/8). You can specify an optional priority to be associated with this router. If this command is not specified, then PIM reverts to the older ASBSR implementation mechanism.

Default

If ip pim bsr-candidate global is not specified, it is the same as if the user had specified the following:

(config)# no ip pim bsr-candidate global

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the router to be a CBSR in global scope, with a priority of 1, on interface fxp1.

(config)# ip pim bsr-candidate fxp1

(config)# ip pim bsr-candidate global priority 1

(config)#

ip pim bsr-candidate group

Name

ip pim bsr-candidate group - specifies a set of multicast groups and optional priorities for which the

router will volunteer to be a Candidate Bootstrap Router (CBSR)

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 394

Syntax

ip pim bsr-candidate group prefix [priority level]?

no ip pim bsr-candidate group prefix [priority level]?

Mode

Global Configuration

Parameters

prefix - a valid IPv4 prefix specified as a.b.c.d/e

priority level - specifies a priority to be associated with the groups for which a router is volunteering to

be a Candidate Bootstrap Router (CBSR) on the given interface. The value of level can be an integer from 0 to 255, inclusive.

Description

Use the ip pim bsr-candidate group command to configure the administratively scoped BSR

mechanism. The admin scope prefix is 239/8. The group range, therefore, can only be within 239/8. In addition, you can optionally specify a priority to associate with the group being configured.

Default

A router does not act as a CBSR for a group by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the router to be a CBSR in the multicast group 239.0.0.0/8. The priority is configured to be 10.

(config)# ip pim bsr-candidate group 239.0.0.0/8 priority 10

ip pim bsr-candidate interval

Name

ip pim bsr-candidate interval - specifies the interval between originating bootstrap messages

Syntax

ip pim bsr-candidate interval time-seconds

no ip pim bsr-candidate interval time-seconds?

Mode

Global Configuration

Parameters

time-seconds - an integer between 1 and 536,870,906, inclusive, specifying a number of seconds

Description

If a router is acting as the elected BSR for a PIM-SM domain, then the ip pim bsr-candidate interval

command specifies the number of seconds the router should wait between successive bootstrap message

transmissions. The negative form of this command, no ip pim bsr-candidate interval, removes the

configured time-seconds value and returns this to its default value of 60 seconds. Note: Specifying a value

for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 395

Default

If a router is acting as the elected BSR, and ip pim bsr-candidate interval is not specified, then it is

the same as if the user had specified the following:

(config)# ip pim bsr-candidate interval 60

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a router is configured to act as a BSR on interface 239.0.0.4. The interval at which the router should wait between bootstrap message transmissions is then configured to be 30 seconds.

(config)# ip pim bsr-candidate 239.0.0.4

(config)# ip pim bsr-candidate interval 30

ip pim bsr-candidate priority

Name

ip pim bsr-candidate priority - specifies the priority to use when configuring a router to be a

Candidate Bootstrap Router (CBSR) on an interface or group

Syntax

ip pim bsr-candidate priority level

no ip pim bsr-candidate priority level?

Mode

Global Configuration

Parameters

level - an integer from 0 to 255, inclusive

Description

Use the ip pim bsr-candidate priority command to specify a priority to be associated with the

interface or groups for which a router is volunteering to be a CBSR. When more than one router attached to a network attempts to become the CBSR, the one with the highest priority wins. (Note that this is different than the CRP priority.)

The negative form of this command, no ip pim bsr-candidate priority, removes the configured level

and returns this to its default value of 0. Note: Specifying a value for level in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If a router is acting as the elected BSR, and ip pim bsr-candidate priority is not specified, then it is

the same as if the user had specified the following:

(config)# ip pim bsr-candidate priority 0

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a router is configured to act as a BSR on interface 239.0.0.4. The priority is then configured to be 5.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 396

(config)# ip pim bsr-candidate 239.0.0.4

(config)# ip pim bsr-candidate priority 5

ip pim bsr-holdtime

Name

ip pim bsr-holdtime - specifies the time after which the elected Bootstrap Router (BSR) will be

assumed unreachable when bootstrap messages are not received from it

Syntax

ip pim bsr-holdtime time-seconds

no ip pim bsr-holdtime time-seconds?

Mode

Global Configuration

Parameters

time-seconds - specifies the time, in seconds, between 12 and 1,073,741,823, inclusive

Description

Use the ip pim bsr-holdtime command to configure the length of time that must pass without a BSR

message from the elected BSR before a PIM-SM router considers the elected BSR to be dead. The

negative form of this command, no ip pim bsr-holdtime, removes the configured time-seconds value

and returns this to its default value of 130 seconds. Note: Specifying a value for time-seconds in the no

form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim bsr-holdtime is not specified, it is the same as if the user had specified the following:

(config)# ip pim bsr-holdtime 130

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the BSR holdtime to be 50 seconds.

(config)# ip pim bsr-holdtime 50

ip pim dr-switch-immediate

Name

ip pim dr-switch-immediate - causes a Designated Router (DR) to initiate a switch to the Shortest

Path Tree (SPT) for (S,G) upon receipt of the first data packet from source S

Syntax

ip pim dr-switch-immediate

no ip pim dr-switch-immediate

Mode

Global Configuration

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 397

Parameters

none

Description

The ip pim dr-switch-immediate command configures a Designated Router (DR) to initiate a switch to

the shortest path tree upon receipt of the first data packet received from source S addressed to group G.

The negative form of this command sets the value to the default, which is to switch when the traffic rate exceeds a threshold.

If this option is set, than any other options related to the default method of switching will have no effect. Once this option has been configured, the only way to return to the default mode is to deconfigure it using

the no form.

Default

If ip pim dr-switch-immediate is not specified, it is the same as if the user had specified the following:

(config)# no ip pim dr-switch-immediate

Command History

NGC 2.2 – This command was introduced.

Examples

In the following example, if the router is a DR, then the first time that the router receives a Register message encapsulating data from source S addressed to group G, it will initiate a switch to the SP tree rooted at S.

(config)# ip pim dr-switch-immediate

See Also

"ip pim rp-switch-immediate" ("ip pim rp-switch-immediate" on page 404)

ip pim mrt-spt-multiplier

Name

ip pim mrt-spt-multiplier - together with the mrt-period, specifies the interval at which the data

rate threshold for all S,G entries will be checked for a possible switch to the SP tree

Syntax

ip pim mrt-spt-multiplier number

no ip pim mrt-spt-multiplier number?

Mode

Global Configuration

Parameters

number - an integer between 1 and 100, inclusive

Description

The mrt-spt-multiplier value, multiplied by the mrt-period value, specifies the interval at which the

data rate threshold for all (S,G) entries will be checked for a possible switch to the shortest path tree. If

either the rp-switch-immediate or dr-switch-immediate option is configured, then configuring this

value will have no effect.

The negative form of this command, no ip pim mrt-spt-multiplier, resets the MRT Stale Multiplier to

its default. Note: Specifying a value for number in the no form of this command has no effect on the

configuration. Thus, it is displayed above as optional.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 398

Default

If ip pim mrt-spt-multiplier is not specified, it is the same as if the user had specified the following:

(config)# ip pim mrt-spt-multiplier 4

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the MRT SPT Mult value to be 20.

(config)# ip pim mrt-spt-multiplier 20

See Also

"ip pim dr-switch-immediate" ("ip pim dr-switch-immediate" on page 396)

"ip pim rp-switch-immediate" ("ip pim rp-switch-immediate" on page 404)

ip pim probe-interval

Name

ip pim probe-interval - specifies the number of seconds prior to the RegisterStop timer expiry to send

a null Register message to the Rendezvous Point (RP)

Syntax

ip pim probe-interval time-seconds

no ip pim probe-interval time-seconds?

Mode

Global Configuration

Parameters

time-seconds - specifies the time, in seconds, between 0 and "ip pim register-suppression-timeout" ("ip pim

register-suppression-timeout" on page 399), inclusive

Description

When PIM null Register messages are used, ip pim probe-interval specifies the number of seconds

prior to the RegisterStop timer expiry to send a null Register message to the Rendezvous Point (RP). If a PIM RegisterStop message is received from the RP before the RegisterStop timer expires, the RegisterStop timer is reset, and the sending of encapsulating Register messages is delayed.

The negative form of this command, no ip pim probe-interval, returns this to its default value of 5

seconds. Note: Specifying a value for time-seconds in the no form of this command has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If ip pim probe-interval is not explicitly configured, it is the same as if the user had specified the

following:

(config)# ip pim probe-interval 5

Command History

NGC 2.2 - This command was introduced.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 399

Examples

The following example configures the probe interval to be 6 seconds.

(config)# ip pim probe-interval 6

ip pim register-suppression-timeout

Name

ip pim register-suppression-timeout - specifies the time, in seconds, between receiving a PIM

RegisterStop message and allowing Register messages encapsulating multicast data to again be sent

Syntax

ip pim register-suppression-timeout time-seconds

no ip pim register-suppression-timeout time-seconds?

Mode

Global Configuration

Parameters

time-seconds - specifies the time, in seconds, between 1 and 3600, inclusive

Description

When a router receives a RegisterStop message from a Rendezvous Point (RP) for an (S,G) pair, it must stop sending multicast data encapsulated in Register messages for some period of time. Such a router is

said to be "register-suppressed" for the (S,G) pair. The ip pim register-suppression-timeout

command specifies the number of seconds for which the router remains register-suppressed. A lower value means that the RP receives more frequent bursts of encapsulated multicast data, while a higher value means a longer join latency for new receivers. (Note that if null Registers are sent every "ip pim probe-interval" ("ip pim probe-interval" on page 398) seconds before the timeout, then Register bursts are

prevented, and register-suppression-timeout can then be lowered to decrease join latency.)

The negative form of this command, no ip pim register-suppression-timeout, returns this to its

default value of 60 seconds. Note: Specifying a value for time-seconds in the no form of this command has

no effect on the configuration. Thus, it is displayed above as optional.

Default

If ip pim register-suppression-timeout is not specified, it is the same as if the user had specified

the following:

(config)# ip pim register-suppression-timeout 60

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the PIM sparse mode protocol on interface fxp1. The Register Suppression Timeout is configured to be 70 seconds.

(config)# ip pim register-suppression-timeout 70

ip pim rp-address

Name

ip pim rp-address - configures the router to be a Static Rendezvous Point (static RP)

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 400

Syntax

ip pim rp-address address group prefix

no ip pim rp-address address group prefix

Mode

Global Configuration

Parameters

address - a valid IPv4 address

group prefix - a valid IPv4 multicast group range

Description

Advanced Routing Suite provides two mutually exclusive methods for RP set distribution: statically

configured RPs and Bootstrap Router (BSR). The ip pim rp-address command lets you statically

configure an RP set. Multiple ip pim rp-address commands can be used to add elements to the set.

Defaults

A static RP address is not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, RP 192.168.10.4 is configured to serve multicast group 224.40.2.1, while 192.168.10.10 is configured to serve all other multicast groups. RP 192.168.10.4 is then de-configured, causing 192.168.10.10 to serve all groups.

(config)# ip pim rp-address 192.168.10.4 group 224.40.2.1/32

(config)# ip pim rp-address 192.168.10.10 group 224.0.0.0/4

(config)# no ip pim rp-address 192.168.10.4 group 224.40.2.1/32

(config)#

ip pim rp-candidate

Name

ip pim rp-candidate - configures the router to be a Candidate Rendezvous Point (CRP) on a specified

interface

Syntax

ip pim rp-candidate interface

no ip pim rp-candidate interface?

Mode

Global Configuration

Parameters

interface - a physical interface name or a valid IPv4 address

Description

The ip pim rp-candidate command configures a router to be a Candidate Rendezvous Point (CRP).

Only one interface can be configured as the CRP. A router is chosen as the RP for a multicast group from

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 401

the set of CRPs via a well-known hash function. A CRP's suitability for a given multicast group may be biased with a priority. When choosing an RP for a group from the set of CRPs, the hash function is computed for each member of the set of CRPs with the lowest priority for the group. The CRP yielding the highest hash value is selected as the RP for the group.

The negative form of this command, no ip pim rp-candidate, removes the configured interface. Note:

Specifying a value for interface in the no form has no effect on the configuration. It will not remove other RP

candidate configurations, such as priority or advertisement interval. Thus, it is displayed above as optional.

Default

A router does not act as a CRP on an interface by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the router to be a CRP on interface fxp0.

(config)# ip pim rp-candidate fxp0

(config)#

ip pim rp-candidate advertisement-interval

Name

ip pim rp-candidate advertisement-interval - sets the interval at which a Candidate

Rendezvous Point (CRP) will send CRP Advertisement (Adv) messages to the Bootstrap Router (BSR)

Syntax

ip pim rp-candidate advertisement-interval time-seconds

no ip pim rp-candidate advertisement-interval time-seconds?

Mode

Global Configuration

Parameters

time-seconds - an integer between 1 and 65535, inclusive, specifying a number of seconds

Description

When using the BSR mechanism to distribute RP set information throughout a PIM-SM domain, CRPs must

periodically send C-RP-Adv messages to the BSR. The ip pim rp-candidate

advertisement-interval command is used to specify the time, in seconds, between successive

C-RP-Adv messages.

The negative form of this command, no ip pim rp-candidate advertisement-interval, removes

the configured time-seconds value and returns this to its default value of 60 seconds. Note: Specifying a

value for time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If a router is acting as the elected CRP, and ip pim rp-candidate advertisement-interval is not

specified, then it is the same as if the user had specified the following:

(config)# ip pim rp-candidate advertisement-interval 60

Command History

NGC 2.2 - This command was introduced.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 402

Examples

In the following example, a router is configured to act as a CRP on interface 192.168.3.20. The interval at which the router will send C-RP-Adv messages to the BSR is then configured to be 30 seconds.

(config)# ip pim rp-candidate 192.168.3.20

(config)# ip pim rp-candidate advertisement-interval 30

(config)#

ip pim rp-candidate group

Name

ip pim rp-candidate group - specifies a set of multicast groups and optional priorities for which the

router will volunteer to be a Candidate Rendezvous Point (CRP)

Syntax

ip pim rp-candidate group prefix/len [priority level]?

no ip pim rp-candidate group prefix/len [priority level]?

Mode

Global Configuration

Parameters

prefix/len - a valid IPv4 prefix and mask length within 224.0.0.0/4

priority level - specifies a priority to be associated with the groups for which a router is volunteering to

be a Candidate Bootstrap Router (CBSR) on the given interface. The value of level can be an integer from 0 to 255, inclusive.

Description

Use the ip pim rp-candidate group command to configure a set of multicast groups and optional

priorities for which the router will volunteer to be a CRP. To configure a CRP to volunteer for multiple group ranges, issue the command multiple times, giving different ranges.In addition, you can optionally specify a priority to associate with the group being configured.

Default

A router does not act as a CRP for a group by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures the router to be a CRP in the multicast group 224.0.1.0/24. The priority is configured to be 10.

(config)# ip pim rp-candidate group 224.0.1.0/24 priority 10

Example 2

The following example configures the router to be a CRP in the multicast group 224.1.0.1/32.

(config)# ip pim rp-candidate group 224.1.0.1/32

(config)#

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 403

ip pim rp-candidate holdtime

Name

ip pim rp-candidate holdtime - specifies the holdtime, in seconds, advertised in Candidate

Rendezvous Point Advertisement (C-RP-Adv) messages

Syntax

ip pim rp-candidate holdtime time-seconds

no ip pim rp-candidate holdtime time-seconds?

Mode

Global Configuration

Parameters

time-seconds - specifies the time, in seconds, between 1 and 65535, inclusive

Description

For CRPs, ip pim rp-candidate holdtime specifies the holdtime advertised in C-RP-Adv messages

and is used by the Bootstrap Router (BSR) to time out RPs. The negative form of this command, no ip pim

rp-candidate holdtime, removes the configured time-seconds value and returns this to its default value

of 150 seconds. Note: Specifying a value for time-seconds in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Defaults

If ip pim rp-candidate holdtime is not specified, it is the same as if the user had specified the

following:

(config)# ip pim rp-candidate holdtime 150

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a router is configured to act as a CRP on interface 192.168.3.20. The holdtime is then configured to be 100 seconds.

(config)# ip pim rp-candidate 192.168.3.20

(config)# ip pim rp-candidate holdtime 100

(config)#

ip pim rp-candidate priority

Name

ip pim rp-candidate priority - specifies the priority to use when configuring a router to be a

Candidate Rendezvous Point (CRP) on an interface or group

Syntax

ip pim rp-candidate priority level

no ip pim rp-candidate priority level?

Mode

Global Configuration

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 404

Parameters

level - an integer from 0 to 255, inclusive

Description

When using the BSR method of RP set distribution, CRPs will periodically send C-RP-Adv messages to the BSR. These messages specify a set of groups for which the CRP is volunteering to be an RP. In addition, a priority is associated with each set of groups and is used to decide which CRP will actually serve as the RP for a given group. When more than one router attached to a network attempts to become the CRP, the one with the lowest priority wins. (Note that this is different than the BSR priority.)

The negative form of this command, no ip pim rp-candidate priority, removes the configured level

and returns this to its default value of 0. Note: Specifying a value for level in the no form has no effect on

the configuration. Thus, it is displayed above as optional.

Default

If a router is acting as the elected CRP, and is not specified, then it is the same as if the user had specified the following:

(config)# ip pim rp-candidate priority 0

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, a router is configured to act as a CRP on interface 192.168.3.20. The priority is then configured to be 5.

(config)# ip pim rp-candidate 192.168.3.20

(config)# ip pim rp-candidate priority 5

(config)#

ip pim rp-switch-immediate

Name

ip pim rp-switch-immediate - causes a Rendezvous Point (RP) to initiate a switch to the Shortest

Path (SP) tree for (S,G) upon receipt of the first Register message encapsulating data from source S

Syntax

ip pim rp-switch-immediate

no ip pim rp-switch-immediate

Mode

Global Configuration

Parameters

none

Description

The PIM-SM protocol allows an RP or a Designated Router (DR) to switch from receiving data from a source S sent to a group G via the RP tree, to receiving data from the SP tree. Two methods are available within Advanced Routing Suite for deciding when an SP tree switch should be initiated. One of these methods is to initiate a switch to the SP tree for an (S,G) pair upon receipt of the first Register message containing data from source S addressed to group G.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 405

If the ip pim rp-switch-immediate command is not configured, then an active RP will initiate a switch

to the SP tree when the traffic rate exceeds a threshold.

If this option is set, then any other options related to the default method of switching will have not effect.

Once this option is configured, the only way to return to the default mode is to deconfigure it using the no

form.

Defaults

The default is to switch when the traffic rate exceeds a threshold. Thus, if ip pim rp-switch-immediate

is not specified, it is the same as if the user had specified the following:

(config)# no ip pim rp-switch-immediate

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if this router is an RP for G, then the first time that the router receives a Register message encapsulating data from source S addressed to group G, it will initiate a switch to the SP tree rooted at S.

(config)# ip pim rp-switch-immediate

See Also

"ip pim dr-switch-immediate" ("ip pim dr-switch-immediate" on page 396)

ip pim sparse-mode

Name

ip pim sparse-mode - enables PIM sparse mode on an interface

Syntax

ip pim sparse-mode

no ip pim sparse-mode

Mode

Interface Configuration

Parameters

none

Description

The ip pim sparse-mode command enables PIM sparse mode on the associated interface. The negative

form of this command, no ip pim sparse-mode, disables PIM-SM on the interface.

Default

PIM sparse mode is disabled by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the PIM sparse mode protocol on interface fxp0.

(config)# interface fxp0

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 406

(config-if)# ip pim sparse-mode

(config-if)# exit

(config)#

ip pim threshold

Name

ip pim threshold - specifies the threshold, in bytes per second, which, when exceeded for an (S,G) pair,

initiates a switch to the Shortest Path (SP) tree

Syntax

ip pim threshold bps

no ip pim threshold bps?

Mode

Global Configuration

Parameters

bps - an integer between 1 and 4,294,967,295, inclusive

Description

The ip pim threshold command configures the threshold, in bytes per second, which, when exceeded

for an (S,G) pair, triggers a switch to the shortest path tree rooted at S. If either the

rp-switch-immediate or dr-switch-immediate option is configured, then configuring this option has

no effect.

The negative form of this command returns the value to the default of 1000 bps. Note: Specifying a value for

bps in the no form of this command has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If ip pim threshold is not specified, it is the same as if the user had specified the following:

(config)# ip pim threshold 1000

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the threshold to be 2000.

(config)# ip pim threshold 2000

See Also

"ip pim dr-switch-immediate" ("ip pim dr-switch-immediate" on page 396)

"ip pim rp-switch-immediate" ("ip pim rp-switch-immediate" on page 404)

"ip pim threshold-dr" ("ip pim threshold-dr" on page 407)

"ip pim threshold-rp" ("ip pim threshold-rp" on page 407)

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 407

ip pim threshold-dr

Name

ip pim threshold-dr - specifies the threshold, in bytes per second, for a Designated Router (DR),

which, when exceeded for an (S,G) pair, initiates a switch to the Shortest Path (SP) tree

Syntax

ip pim threshold-dr bps

no ip pim threshold-dr bps?

Mode

Global Configuration

Parameters

bps - an integer between 1 and 4,294,967,295, inclusive

Description

The ip pim threshold-dr command specifies the threshold, in bytes per second, for a Designated

Router (DR), which, when exceeded for an (S,G) pair, triggers a switch to the shortest path tree. If either the

rp-switch-immediate or dr-switch-immediate option is configured, then configuring this option has

no effect.

The negative form of this command returns the value to the default of 1000 bps. Note: Specifying a value for

bps in the no form of this command has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If ip pim threshold-dr is not specified, it is the same as if the user had specified the following:

(config)# ip pim threshold-dr 1000

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if this router is a DR for the pair (S,G), then the data from S addressed to G must exceed an average of 2000 bytes per second before an SPT switch is initiated.

(config)# ip pim threshold-dr 2000

See Also

"ip pim dr-switch-immediate" ("ip pim dr-switch-immediate" on page 396)

"ip pim rp-switch-immediate" ("ip pim rp-switch-immediate" on page 404)

"ip pim threshold" ("ip pim threshold" on page 406)

"ip pim threshold-rp" ("ip pim threshold-rp" on page 407)

ip pim threshold-rp

Name

ip pim threshold-rp - specifies the threshold, in bytes per second, for a Rendezvous Point (RP), which,

when exceeded for an (S,G) pair, initiates a switch to the Shortest Path (SP) tree

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 408

Syntax

ip pim threshold-rp bps

no ip pim threshold-rp bps?

Mode

Global Configuration

Parameters

bps - an integer between 1 and 4,294,967,295, inclusive

Description

The ip pim threshold-rp command specifies the threshold, in bytes per second, for a Rendezvous Point

(RP), which, when exceeded for an (S,G) pair, triggers a switch to the shortest path tree. If either the

rp-switch-immediate or dr-switch-immediate option is configured, then configuring this option has

no effect.

The negative form of this command returns the value to the default of 1000 bps. Note: Specifying a value for

bps in the no form of this command has no effect on the configuration. Thus, it is displayed above as

optional.

Default

If ip pim threshold-rp is not specified, it is the same as if the user had specified the following:

(config)# ip pim threshold-rp 1000

Command History

NGC 2.2 - This command was introduced.

Examples

The following example, if this router is an RP for G, then the data from S addressed to G must exceed an average of 2500 bytes per second before an SPT switch is initiated. If this router is a DR for the pair (S,G), then the same data must exceed an average of 2000 bytes per second before an SPT switch is initiated.

The period over which the average will be calculated will be the mrt-interval times the

mrt-spt-multiplier, or 60 seconds.

(config)# ip pim threshold-rp 2500

(config)# ip pim threshold-dr 2000

(config)# ip pim mrt-interval 30

(config)# ip pim mrt-spt-multiplier 2

See Also

"ip pim dr-switch-immediate" ("ip pim dr-switch-immediate" on page 396)

"ip pim rp-switch-immediate" ("ip pim rp-switch-immediate" on page 404)

"ip pim threshold" ("ip pim threshold" on page 406)

"ip pim threshold-dr" ("ip pim threshold-dr" on page 407)

ip pim trace file

Name

ip pim trace file - specifies the file to receive tracing information, the size of the file, whether to

overwrite existing files, and the maximum number of files allowed

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 409

Syntax

ip pim trace file file_name [max-size file_size[M | m | K | k]? || max-files num_files || no-timestamp || overwrite]?

no ip pim trace file file_name [max-size file_size[M | m | K | k]? || max-files num_files || no-timestamp || overwrite]?

Mode

Global Configuration

Parameters

file_name - specifies the name of the file to receive the tracing information. Note that the file name is not

specified in quotes.

max-size file_size[M | m | K | k] - specifies the maximum file size in bytes (by default) or megabytes

or kilobytes. The acceptable value range is 10K to 4,294,967,295 bytes. Notice that there is no space

between the file_size parameter and the unit type.

max-files num_files - specifies the maximum number of files allowed in the directory. The acceptable

value range is 2 to 4,294,967,295, with a default value of 4,294,967,295 files.

no-timestamp - specifies that a timestamp should not be prepended to all trace lines

overwrite - specifies to begin tracing by appending or truncating an existing file

Description

The trace file command is associated with each protocol, so that information pertaining to a single

protocol can be written to its own file. The ip pim trace file command specifies a file for tracing of all

PIM events. The negative form of this command disables this tracing. The specific events that are traced are

controlled by the ip pim trace flag command.

The max-size option sets a maximum on the size of the trace file. The size can be specified in

megabytes by giving 'M' or 'm' (without a leading space), or it can be specified in kilobytes by giving 'K' or 'k'. If no units are given, the size is assumed to be in bytes. The range of this parameter is 10K to 2^32-1 bytes (about 4294M). When the maximum file size is reached, the file is closed and renamed to fname.0, then

fname.1, and so on, until the maximum number of files specified by the max-files option is reached. The

default is unlimited. The size of a trace file is limited by the file system on which the trace file resides.

The max-files option specifies the maximum number of files allowed in the specified directory. The range

of this parameter is 2 to 4,294,967,295. The default is 4,294,967,295 files.

The no-timestamp option disables the pre-pending of a timestamp to all lines written to the trace file. The

default is to prepend a timestamp to all lines written to a trace file.

The overwrite option specifies whether to start tracing by truncating or appending to an existing file.

Note: These options are not cumulative across multiple commands. Consider the following example:

(config)# ip pim trace file /var/log/pim.log no-timestamp

(config)# ip pim trace file /var/log/pim.log max-files 10

The option given in the second command completely replaces that given in the first. In order to specify both

no-timestamp and max-files 10, they must be entered on the same line as follows.

(config)# ip pim trace file /var/log/pim.log max-files 10 no-timestamp

Default

PIM tracing is turned off by default.

Command History

NGC 2.2 - This command was introduced.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 410

Examples

In the following example, PIM tracing is written to the file "/var/tmp/pim.log". The maximum size of the file is configured to be 1024 KB, and the maximum number of files permitted is 3. When the file reaches 1 megabyte in size (the maximum size in this configuration), the file is renamed to pim.log.0, and pim.log is re-created. When the next pim.log file reaches 1 megabyte in size, pim.log.0 is renamed pim.log.1, pim.log is renamed pim.log.0, and pim.log is re-created. This continues until four log files exist (the maximum allowed in this configuration). No timestamp will display at the beginning of the trace lines.

(config)# ip pim trace file /var/tmp/pim.log max-size 1024k max-files 4 no-timestamp

ip pim trace flag

Name

ip pim trace flag - specifies PIM-specific tracing options as well as options that are common across all

protocols

Syntax

ip pim trace flag ( [ route | normal | state | policy | task | timer | all | debug ] ) | ( [ packets | assert | bsr | hello | register | jp ] [ send | receive | send-receive ]? [detail?] )

no ip pim trace flag ( [ route | normal | state | policy | task | timer | all ] ) | ( [ packets | assert | bsr | hello | register | debug | jp ] [ send | receive | send-receive ]? [detail?] )

Mode

Global Configuration

Parameters

Flags common to all protocols:

[ route | normal | state | policy | task | timer | all ] - These tracing flags are common

to all protocols. They cannot be associated with a send, receive, or send-receive action item. Similarly, you cannot specify to show detailed information when tracing these flags. These flags are defined as follows:

route - trace routing table changes for routes installed by this protocol or peer

normal - trace normal protocol occurrences. Note: Abnormal protocol occurrences are always traced.

state - trace state machine transition in the protocol

policy - trace the application of protocol and user-specified policy to routes being imported or exported

task - trace system interface and processing associated with this protocol

timer - trace timer usage by this protocol

all - turns on all trace flags

PIM-specific flags that do not allow associated action items:

[ debug ] - This PIM-specific flag cannot be associated with the send, receive, or send-receive action

items. This flag is defined as follows:

debug - extra trace information of use mainly to developers

IM-specific flags that allow associated action items:

[ packets | assert | hello | bsr | register | jp ] - These PIM-specific flags can be associated

with the send, receive, or send-receive action items. These flags are defined as follows:

packets - specifies to trace all types of PIM packets

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 411

assert - specifies to trace PIM Assert packets

hello - specifies to trace PIM Hello packets

bsr - specifies to trace BSR packets

jp - specifies to trace Join/Prune message packets

register - specifies to trace all Register message packets

[ send | receive | send-receive ]? - optionally specify whether to limit the tracing to packets sent,

received, or both

[detail?] - optionally specify to use a more verbose format when displaying information about the

contents of packets instead of one or two lines

Description

Use the ip pim trace flag command to specify tracing flags for PIM-SM, tracing. Each flag must reside

on its own configuration line. For example, you cannot specify to trace both jp and bsr packets in the same command.

Default

The default is for no flags to be explicitly configured.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, trace flags specify that both the sent and received register and jp messages are traced in detail. This tracing information will be written to the file /var/tmp/pim.log.

(config)# ip pim trace file /var/tmp/pim.log

(config)# ip pim trace flag register send-receive detail

(config)# ip pim trace flag jp send-receive detail

ip pim whole-packet-checksum

Name

ip pim whole-packet-checksum - specifies that checksums in Register messages should be calculated

over the entire encapsulated data packet, rather than just over the Register message header

Syntax

ip pim whole-packet-checksum

no ip pim whole-packet-checksum

Mode

Global Configuration

Parameters

none

Description

Previous versions of the PIM-SM specification had the checksum of Register messages calculated over the entire message, including encapsulated data. The latest version of the specification states that the checksum should be calculated only over the Register message header, not any encapsulated data. This is

Advanced Routing Suite's default checksum method. Use the ip pim whole-packet-checksum

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 412

command to specify that checksums in Register messages should be calculated according to the old method.

Defaults

The default is to calculate checksums over the Register message header only. Thus, if ip pim

whole-packet-checksum is not specified, it is the same as if the user had specified the following: (config)# no ip pim whole-packet-checksum

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the PIM sparse mode protocol on interface fxp1. When encapsulating data from local sources in Register messages and sending them to the Rendezvous Point on interface fxp1, the message checksum will be calculated over the entire encapsulated packet, rather than just over the Register message header.

(config)# ip pim whole-packet-checksum

show ip pim bsr-router

Name

show ip pim bsr-router - displays the bootstrap router (BSR)

Syntax

show ip pim bsr-router

Mode

User Execution

Parameters

none

Description

Use the show ip pim bsr-router query to view information about the router’s BSR status.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns information as a result of the BSR query.

> show ip pim bsr-router

PIMv2 Bootstrap Information This system is the Bootstrap Router (BSR) BSR address: 224.1.8.4 Uptime: 00:03:53, BSR Priority: 0, Hash Mask Length: 30 Next bootstrap message in 00:00:13

show ip pim cbsr

Name

show ip pim cbsr - shows this router’s candidate bootstrap router (CBSR) information

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 413

Syntax

show ip pim cbsr

Mode

User Execution

Parameters

none

Description

Use the show ip pim cbsr query to obtain information about the router’s CBSR status.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays PIM CBSR information.

> show ip pim cbsr

PIMv2 Candidate Bootstrap information CBSR address: 224.2.2.2 CBSR Priority: 0, Hash mask length: 0 CBSR State: elected

show ip pim rp

Name

show ip pim rp - displays rendezvous point (RP) set information

Syntax

show ip pim rp

Mode

User Execution

Parameters

none

Description

Use the show ip pim rp query to obtain information about the RP set that is currently in use.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns information about the RP set currently in use.

> show ip pim rp

The PIM RP Set Group: 224.0.0.0/4 RP: 10.1.1.1 Uptime: 00:04:10, Expires: 00:02:20, Priority: 0

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 414

show ip pim rp-candidate

Name

show ip pim rp-candidate - displays this router’s candidate rendezvous point (CRP) information

Syntax

show ip pim rp-candidate

Mode

User Execution

Parameters

none

Description

Use the show ip pim rp-candidate query to obtain information about the router’s CRP status.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns information about this router’s CRP status.

> show ip pim rp-candidate

Candidate RP information Candidate RP address 10.2.2.2 CRP Holdtime: 150 seconds Group: 224.2.0.0/8 Priority 0

show ip pim rp-hash

Name

show ip pim rp-hash - displays the rendezvous point (RP) to which a group hashes

Syntax

show ip pim rp-hash ipv4_address

Mode

User Execution

Parameters

ipv4_address - specify a valid IPv4 multicast group address specified in dotted-quad format

Description

Use the show ip pim rp-hash query to view the RP to which a specified multicast group hashes.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example displays the RP to which address 224.2.2.8 hashes.

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 415

> show ip pim rp-hash 224.2.2.8

RP 10.1.2.3

show ip pim sparse-mode join-prune xmit

Name

show ip pim sparse-mode join-prune xmit - displays sparse mode join/prune transmission

information

Syntax

show ip pim sparse-mode join-prune xmit

Mode

User Execution

Parameters

none

Description

Use the show ip pim sparse-mode join-prune xmit query to view information about sparse mode

join/prune transmissions.

Command History

NGC 2.2 - This command was introduced

Examples

The following example returns sparse mode join/prune transmission information.

> show ip pim sparse-mode join-prune xmit

Neighbor address: 10.1.2.3 Via interface: fxp1 Next message in 335 seconds Group: 224.3.2.1 Join: 10.24.16.0/4 RPT

show ip pim sparse-mode mrt

Name

show ip pim sparse-mode mrt - displays detailed information about S,G entries

Syntax

show ip pim sparse-mode mrt [ group group-prefix || source source-prefix ]?

Mode

User Execution

Parameters

group group-prefix - optionally specify a group prefix in the format a.b.c.d/e

source source-prefix - optionally specify a source prefix in the format a.b.c.d/e

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 416

Description

The show ip pim sparse-mode mrt query displays detailed information about PIM-SM S,G entries in the

Multicast Routing Table. The query shows all S,G entries by default, or you can specify a single group and/or source.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows a request for all MRT information.

> show ip pim sparse-mode mrt

PIM Sparse Mode Multicast Routing Table

Flags: E - Entry forwarding on the RPT, J - Joining to the SPT, N - No flags set, R - RPT bit is set, S - SPT bit is set, W - Wildcard entry, X - External component interest

224.1.1.1 192.168.10.1 uptime 01:02:09, flags: S Incoming interface: fxp1, index 2, vif 1 Outgoing interface list: fxp2, index 3, vif 2 fxp3, index 4, vif 3

192.168.121.1 uptime 12:12:12, flags: S Incoming interface: fxp2, index 3, vif 2 Outgoing interface list: fxp1, index 2, vif 1

226.2.2.2 * uptime 02:03:24, flags: N Incoming interface: null Outgoing interface list: fxp2, index3, vif 2

10.1.1.1 uptime 00:10:13, flags S Incoming interface: fxp3, index 4, vif 3 Outgoing interface list: fxp2, index 3, vif 2

Field Descriptions

The following table describes the fields that appear in the PIM-SM MRT Detail Information Query.

PIM-SM MRT Detail Information Query Fields

Field Description

224.1.1.1 (and other top level IPv4 addresses)

Address of multicast group

10.1.1.1 (and other IPv4 address below multicast group address)

IP address of source

uptime Amount of time the entry has existed

Protocol Independent Multicast - Sparse Mode (PIM-SM)

Protocol Independent Multicast (PIM) Page 417

Field Description

flags Indicates any flags that are set.

fxp3 (and other physical interfaces) The physical interface name

index The interface index

vif The interface vif number

Page 418

Chapter 20

Access Lists

In This Chapter

Access Lists Overview 418

access-list 418

access-list sequence-number 420

ip access-list sequence-number 421

ip access-list standard 422

permit | deny 422

show access-list 424

show ip access-list 425

Access Lists Overview Access lists specify a collection of permit and deny conditions that apply to prefixes. They perform a sequential lookup and return the first matched entry as the true match. Access lists are referred to by name from other configuration elements, such as route maps and distribute lists. The assigned name must be unique among all other access lists.

access-list

Name

access-list - configures an access list

Syntax

access-list list_id [seq seq_value]? [deny | permit] [(ip4_addr (wildcard)?] ?

no access-list list_id [seq seq_value]? [[deny | permit] [ ip4_addr (wildcard)?] ?

Mode

Global Configuration

Parameters

list_id - specify a string of characters for this access list name

seq seq_value - this is specified as an integer between 0 and 65535, inclusive. Note: Sequence numbers

are generated automatically in increments of 5 unless automatic generation is turned off. If automatic generation is disabled, then the sequence number must be specified. (See "access-list sequence-number" ("access-list sequence-number" on page 420) for more information on automatic generation.) Otherwise, specifying this command is optional.

deny | permit - denies or permits the specified source address

access-list

Access Lists Page 419

[ip4_addr (wildcard)?] - specify a valid IPv4 address with an optional wildcard to be included in this

access list

Description

Use the access-list command to configure an access list. List entries are in the order specified by their

sequence number. The first match determines whether the address is permitted or denied. If no conditions match, then the policy engine declares it as a failed match.

Every entry in the Access List is associated with a permit/deny indicator. It is used to indicate to the

filter/route-map containing the list as a match element whether the match element succeeded or not. A

permit indicates a successful match whereas a deny result causes the match element to fail.

When creating an access list, by default, the end of the access list contains an implicit deny statement for everything. Further, if a wildcard is omitted from an associated IPv4 host address access list specification,

0.0.0.0 is assumed to be the wildcard.

Use the negative form of this command to delete all entries or specific entries in an access list. One way to remove a specific entry from an access list is to specify all parameters that were specified when the entry was created. Another way is to specify the sequence number of the entry, which is either automatically generated or explicitly configured.

Default

Access lists are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures an access list called "abc" that denies all prefixes matching 128.0.0.0/8.

(config)# access-list abc deny 128.0.0.0 0.255.255.255

Example 2

The following example configures three entries in access list number 1. The first list entry permits the single address 10.11.0.12. The second list entry denies all other addresses in 10.11/16. The third entry permits all addresses in 10/8.

(config)# access-list 1 permit 10.11.0.12 0.0.0.0

(config)# access-list 1 deny 10.11.0.0 0.0.255.255

(config)# access-list 1 permit 10.0.0.0 0.255.255.255

Example 3

The following example deletes the first entry configured in access list number 1, shown in Example 2.

(config)# no access-list 1 permit 10.11.0.12 0.0.0.0

Example 4

The following example shows another way to delete the first entry configured in access list number 1, shown in Example 2.

(config)# no access-list 1 seq 5

See Also

"access-list sequence-number" ("access-list sequence-number" on page 420)

"access-list sequence-number" ("access-list sequence-number" on page 420)

access-list sequence-number

Access Lists Page 420

access-list sequence-number

Name

access-list sequence-number - specifies whether Advanced Routing Suite should use automatic

sequence numbering when configuring access lists

Syntax

access-list sequence-number

no access-list sequence-number

Mode

Global Configuration

Parameters

none

Description

Sequence values are generated in increments of 5, with the first sequence value generated being 5, then 10, then 15, and so on. If a sequence value is specified for an entry, and then not specified for subsequent entries, the assigned (generated) sequence values are then incremented in units of 5 based on the highest sequence number present in the list.

Note: Sequence numbers are generated automatically in increments of 5 unless automatic generation is turned off. If automatic generation is disabled, then the sequence number must be specified. Otherwise,

specifying this command is optional. Use the negative form of the sequence command, no access-list

sequence-number, to turn off automatic sequence number generation.

Default

Sequence numbers are generated automatically by Advanced Routing Suite. Therefore, if access-list

sequence-number is not specified, it is the same as if the user had specified the following:

(config)# access-list sequence-number

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures four entries in access list "abc." The first entry explicitly configures sequence number 3. The two subsequent entries will, therefore, have automatically generated sequence numbers of 8 and 13 respectively. Sequence numbering is then turned off; therefore, sequence numbers must be explicitly configured for the remainder of the access list.

(config)# access-list abc seq 3 permit 10.11.0.12 0.0.0.0

(config)# access-list abc deny 10.11.0.0 0.0.255.255

(config)# access-list abc permit 10.0.0.0 0.255.255.255

(config)# no access-list sequence-number

(config)# access-list abc seq 20 permit 192.168.0.0 0.0.255.255

ip access-list sequence-number

Access Lists Page 421

ip access-list sequence-number

Name

ip access-list sequence-number - specifies whether Advanced Routing Suite should use automatic

sequence numbering when configuring access lists in Standard ACL Configuration mode

Syntax

ip access-list sequence-number

no ip access-list sequence-number

Mode

Global Configuration

Parameters

none

Description

Sequence values are generated in increments of 5, with the first sequence value generated being 5, then 10, then 15, and so on. If a sequence value is specified for an entry, and then not specified for subsequent entries, the assigned (generated) sequence values are then incremented in units of 5 based on the highest sequence number present in the list.

Note: Sequence numbers are generated automatically in increments of 5 unless automatic generation is turned off. If automatic generation is disabled, then the sequence number must be specified. Otherwise,

specifying this command is optional. Use the negative form of the sequence command, no ip

access-list sequence-number, to turn off automatic sequence number generation.

Default

Sequence numbers are generated automatically by Advanced Routing Suite. Therefore, if ip

access-list sequence-number is not specified, it is the same as if the user had specified the following:

(config)# ip access-list sequence-number

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures four entries in access list "abc." The first entry explicitly configures sequence number 3. The two subsequent entries will, therefore, have automatically generated sequence numbers of 8 and 13 respectively. Sequence numbering is then turned off; therefore, sequence numbers must be explicitly configured for the remainder of the access list.

(config)# ip access-list standard abc

(config-std-nacl)# seq 3 permit 10.11.0.12 0.0.0.0

(config-std-nacl)# deny 10.11.0.0 0.0.255.255

(config-std-nacl)# permit 10.0.0.0 0.255.255.255

(config-std-nacl)# exit

(config)# no ip access-list sequence-number

(config)# ip access-list standard abc

(config-std-nacl)# seq 20 permit 192.168.0.0 0.0.255.255

(config-std-nacl)# exit

(config)#

ip access-list standard

Access Lists Page 422

ip access-list standard

Name

ip access-list standard - enters standard configuration mode for a specified access list

Syntax

ip access-list standard list_name

Mode

Global Configuration

Parameters

list_name - specify a string of characters for this access list name

Description

Use ip access-list standard command to enter Standard Access List Configuration mode. This

configuration mode provides an alternative to configuring access lists using the access-list command

in Global Configuration mode.

Default

none

Command History

NGC 2.2 - This command was introduced.

Examples

The following example enters standard access list configuration mode for the access list labeled abc.

(config)# ip access-list standard abc

(config-std-nacl)#

permit | deny

Name

permit | deny - specifies whether to allow or deny entries in an access list

Syntax

[seq seq_value] [deny | permit] [ (ip4_addr [wildcard]? ]

no [seq seq_value] [deny | permit] [ (ip4_addr [wildcard]?]?

Mode

Standard ACL Configuration

Parameters

seq seq_value - this is specified as an integer between 0 and 65535, inclusive. Note: Sequence numbers

are generated automatically in increments of 5 unless automatic generation is turned off. If automatic generation is disabled, then the sequence number must be specified. Otherwise, specifying this command is optional.

permit | deny

Access Lists Page 423

deny | permit - denies or permits the specified access list

(ipv4_addr [wildcard]?) - specify a valid IPv4 address with an optional wildcard to be included in this

access list

Description

Use the above access lists commands in ACL Configuration Mode to configure an access list for the specified entry. Entries are evaluated according to their list entry sequence. The first match determines whether the address is permitted or denied. If no conditions match, then the policy engine declares it as a failed match.

Every entry in the Access List is associated with a permit/deny indicator. It is used to indicate to the

filter/route-map containing the list as a match element whether the match element succeeded or not. A

permit indicates a successful match whereas a deny result causes the match element to fail.

When creating an access list, by default, the end of the access list contains an implicit deny statement for everything. Further, if a wildcard is omitted from an associated IPv4 host address access list specification, then 0.0.0.0 is assumed to be the wildcard.

Use the negative form of this command to delete all entries or specific entries in an access list. One way to remove a specific entry from an access list is to specify all parameters that were specified when the entry was created. Another way is to specify the sequence number of the entry, which is either automatically generated or explicitly configured.

Default

Access list entries are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures access list "abc" with three entries. The first entry permits the single address 10.11.0.12. The second entry denies all other addresses in 10.11/16. The third entry permits all other addresses in 10/8.

(config)# ip access-list standard abc

(config-std-nacl)# permit 10.11.0.12 0.0.0.0

(config-std-nacl)# deny 10.11.0.0 0.0.255.255

(config-std-nacl)# permit 10.0.0.0 0.255.255.255

(config-std-nacl)# exit

(config)#

Example 2

In the following example, the first list entry from Example 1 is deleted from access list abc.

(config)# ip access-list standard abc

(config-std-nacl)# no permit 10.11.0.12 0.0.0.0

(config-std-nacl)# exit

(config)#

Example 3

The following example shows another way to delete the first entry configured in access list abc, shown in Example 1.

(config)# ip access-list standard abc

(config-std-nacl)# no seq 5

show access-list

Access Lists Page 424

(config-std-nacl)# exit

(config)#

See Also

"ip access-list standard" ("ip access-list standard" on page 422)

show access-list

Name

show access-list - displays information about access lists that were configured in Global Configuration

mode

Syntax

show access-list [ detail | summary ]? [ list_id ]?

Mode

Privileged Execution

Parameters

detail | summary - optionally specify whether you want the query to respond with a more verbose

format. Summary information is returned by default.

list_id - a string of characters or an integer that represents the ID of a configured access list. Specifying this

is optional. Advanced Routing Suite will return information for all configured access lists if a list_id is not

specified.

Description

The show access-list query displays information about all or specific access lists configured in Global

Configuration mode (i.e, using the access-list command). (Use the show ip access-list command

to display information about access lists configured wit the ip access-list command.)

This query has two forms. If it is issued without arguments, then information about all configured access lists is returned. Alternatively, the query can be issued naming a specific access list. In this case, the reply will contain information pertaining only to the referenced access list.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following query is a request for summary information for all configured access lists.

# show access-list

Standard IP access-list acl1: 3 entries seq 3 permit 10.10.0.0, wildcard bits 0.0.255.255 seq 8 deny 10.0.0.0, wildcard bits 0.255.255.255 seq 13 permit 12.12.0.0, wildcard bits 0.0.255.255 Standard IP access-list acl2: 3 entries seq 3 permit 10.11.0.12, wildcard bits 0.0.0.0 seq 10 deny 10.11.0.0, wildcard bits 0.0.255.255 seq 15 permit 10.0.0.0, wildcard bits 0.255.255.255

Example 2

The following query is a request for detail information about a specific access list named "acl1".

show ip access-list

Access Lists Page 425

# show access-list detail acl1

Standard IP access-list acl1: count: 3, sequences 3 - 13 seq 3 permit 10.10.0.0, wildcard bits 0.0.255.255 seq 8 deny 10.0.0.0, wildcard bits 0.255.255.255 seq 13 permit 12.12.0.0, wildcard bits 0.0.255.255

show ip access-list

Name

show ip access-list - displays information about access lists configured in Standard ACL Configuration

mode

Syntax

show ip access-list [ detail | summary ]? [ list_id ]?

Mode

Privileged Execution

Parameters

detail | summary - optionally specify whether you want the query to respond with a more verbose

format. Summary information is returned by default.

list_id - a string of characters or an integer that represents the ID of a configured access list. Specifying this

is optional. Advanced Routing Suite will return information for all configured access lists if a list_id is not

specified.

Description

The show ip access-list query displays information about all or specific access lists configured in

Standard ACL Configuration mode (i.e, using the ip access-list command).

This query has two forms. If it is issued without arguments, then information about all configured access lists is returned. Alternatively, the query can be issued naming a specific access list. In this case, the reply will contain information pertaining only to the referenced access list.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following query is a request for summary information for all configured access lists.

# show ip access-list

Standard IP access-list acl1: 3 entries seq 3 permit 10.10.0.0, wildcard bits 0.0.255.255 seq 8 deny 10.0.0.0, wildcard bits 0.255.255.255 seq 13 permit 12.12.0.0, wildcard bits 0.0.255.255 Standard IP access-list acl2: 3 entries seq 3 permit 10.11.0.12, wildcard bits 0.0.0.0 seq 10 deny 10.11.0.0, wildcard bits 0.0.255.255 seq 15 permit 10.0.0.0, wildcard bits 0.255.255.255

Example 2

The following query is a request for detail information about a specific access list named "acllist1".

show ip access-list

Access Lists Page 426

# show ip access-list detail acllist1

Standard IP access-list acllist1: count: 3, sequences 3 - 13 seq 3 permit 10.10.0.0, wildcard bits 0.0.255.255 seq 8 deny 10.0.0.0, wildcard bits 0.255.255.255 seq 13 permit 12.12.0.0, wildcard bits 0.0.255.255

Page 427

Chapter 21

AS Paths and AS Path Lists

In This Chapter

AS Paths and AS Path Lists Overview 427

ip as-path access-list 428

ip as-path name 429

show ip as-path-access-list 430

show ip bgp paths 431

AS Paths and AS Path Lists Overview An AS path includes a list of autonomous systems that routing information has passed through to get to a specified router and an indicator of the origin of this route. The AS path is used to prevent routing loops in BGP.

This routing information can be used to prefer one path to a destination network over another. The primary method for preferring a route with Advanced Routing Suite is to specify a list of filters to be applied to AS paths when importing and exporting routes.

Each autonomous system through which a route passes prepends its AS number to the beginning of the AS path.

Advanced Routing Suite includes a powerful implementation of AS path regular expressions. The entire AS path regular expression must be contained within the <...> or within (...). The content is read from left to right. The left side matches the beginning of the AS path; the right side matches the end of the AS path. The alphabet (set of valid members) is the valid range of AS numbers, or more specifically, {1 ... 65535}. Also, Advanced Routing Suite supports the following "wildcards" or expressions that can be used to build a regular expression:

. - (period) represents any valid member of the alphabet

* - (asterisk) matches zero or more of the preceding element/expression

+ - (plus sign) matches one or more of the preceding element/expression

# - (pound sign) matches zero or one occurrence of the preceding element/expression

Binary operators:

" " (AND) - any sequence of elements and/or expressions separated by a space (" ")

"|" (OR) - any sequence of elements and/or expressions separated by the vertical line symbol ("|")

The symbols "[]" are used to delimit a set of AS numbers. The set may be a list of AS numbers separated

by a space or a range of AS numbers separated by a dash (-). If the entire list of members is prefixed with a

"^", then the valid members are those not listed in the set. (Because a null string or empty string is not an

instance in the alphabet, AS numbers such as [^808] will not match an empty string.) Examples of AS

path regular expressions follow:

Match any single AS number as the AS path:

"."

Match all AS paths coming from a given AS that start with 808:

"808 .*"

Match all paths that do not end with the given AS numbers but must have at least one AS:

ip as-path access-list

AS Paths and AS Path Lists Page 428

".* [^808 809]"

Match a path that has only valid exterior AS numbers:

"[1-6451]+"

Match 305 808 and exactly one other AS number other than 100:

"305 808 [^100]"

Match 305 808 and any other AS number except 100 or no additional AS. That is, match either 305 808 as the complete path or 305 808 x, where x is any integer other than

100:

"305 808 [^100]"

Match either 808 or 305 with no additional AS numbers in the path:

"305|808"

Note: For users familiar with gated.conf or Advanced Routing Suite XML configuration, some characters that are normally used in regular expressions have special meaning in the Advanced Routing Suite CLI. Therefore, these characters have been substituted by others.

<space> is replaced by an underscore. For example, the regular expressions 808 and 804 are separated by an underscore in the following command: (config)# ip as-path name bar 808_804 any

"?" is replaced by the character "#". For example, the regular expression 808? is replaced by 808# in the following command: (config)# ip as-path name bar 808# any

ip as-path access-list

Name

ip as-path access-list - specifies a BGP AS_PATH regular expression to be used in filtering

Syntax

ip as-path access-list name [ ( [ permit | deny ] regexp origin ) | [ named as-path-name ] ]

no ip as-path access-list name

Mode

Global Configuration

Parameters

name - the name of this AS Path access list specified as a string of characters

permit | deny - specifies whether to allow or reject this AS Path regular expression

regexp - the regular expression

origin - one of either egp, igp, incomplete, or any

named as-path-name - specifies the name of a configured access list

Description

The ip as-path access-list command specifies a BGP AS _PATH regular expression used in filtering.

An AS path access list does nothing until it is referred to in the context of policy. This must be done within a route map and then referred to within a protocol.

The origin specifies whether the route was learned from an EGP source, an IGP source, or another source.

An origin of igp indicates the route was learned from an Intra-Domain Routing Protocol and is most likely

complete. An origin of egp indicates the route was learned from the EGP protocol, and the path is most

ip as-path name

AS Paths and AS Path Lists Page 429

likely not complete. When the route is learned from another source, an origin of incomplete is used. An

origin of any can be used to match any origin.

Default

No AS path access lists are defined by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures an access list named "abc" with two list entries. The first entry permits regular expression 808.* with an origin of any. The second entry denies regular expression 900.* with an origin of any.

(config)# ip as-path access-list abc permit 808.* any

(config)# ip as-path access-list abc deny 909.* any

Example 2

The following example configures an access list named "abc" to apply the regular expression of a configured AS path named "blah."

(config)# ip as-path access-list abc named blah

ip as-path name

Name

ip as-path name - specifies a BGP AS_PATH regular expression to be used in filtering

Syntax

ip as-path name name regexp origin

no ip as-path name name

Mode

Global Configuration

Parameters

name - the name of this AS Path regular expression specified as a string of characters

regexp - the regular expression

origin - one of either egp, igp, incomplete, or any

Description

The ip as-path name command is used to specify a BGP AS _PATH regular expression used in filtering.

An AS path list does nothing until it is referred to in the context of policy. This must be done within a route map and then referred to within a protocol.

The origin specifies whether the route was learned from an EGP source, an IGP source, or another source.

An origin of igp indicates the route was learned from an Intra-Domain Routing Protocol and is most likely

complete. An origin of egp indicates the route was learned from the EGP protocol, and the path is most

likely not complete. When the route is learned from another source, an origin of incomplete is used. An

origin of any can be used to match any origin.

show ip as-path-access-list

AS Paths and AS Path Lists Page 430

Default

No AS paths are defined by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures an AS path regular expression called "bar" that permits regular expression 808.* with an origin of any.

(config)# ip as-path name bar 808.* any

Example 2

The following example configures an AS path regular expression called "bar" that permits regular expression 808.* with an origin of any. The configured AS path regular expression is then referenced in an AS Path Access List configuration.

(config)# ip as-path name bar 808.* any

(config)# ip as-path access-list abc permit named bar

show ip as-path-access-list

Name

show ip as-path-access-list - displays information about BGP access lists

Syntax

show ip as-path-access-list [name]?

Mode

User Execution

Parameters

name - optionally specify a single AS path access list name

Description

Use the show ip as-path-access-list query to obtain information about BGP access lists. If a name is

given, then the information returned pertains only to that access list. If name is not given, then information

about all AS path access lists is returned.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example is a request for information about a single access list called "abc."

> show ip as-path-access-list abc

AS path access list abc deny .* permit 201

show ip bgp paths

AS Paths and AS Path Lists Page 431

Field Descriptions

The following table describes the fields that appear in the BGP AS Path Access List Query.

BGP AS Path Access List Query Fields

Field Description

AS path access list The name of the AS Path Access List

permit/deny Specifies whether the list is permitted or denied, followed by an AS Path regular expression

show ip bgp paths

Name

show ip bgp paths - displays information about BGP AS Paths

Syntax

show ip bgp paths

Mode

User Execution

Parameters

none

Description

Use the show ip bgp paths query to obtain information about all BGP AS Paths.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example returns information for BGP AS Paths.

> show ip bgp paths

Refcount Metric Path 5 50 202 201 200 10 10 200

Field Descriptions

The following table describes the fields that appear in the BGP AS Path Query.

BGP AS Path Query Fields

show ip bgp paths

AS Paths and AS Path Lists Page 432

Field Description

Refcount The number of routes using that path

Metric The MED value for the path

Path The AS Path value

Page 433

Chapter 22

BGP Communities and Community Lists

In This Chapter

BGP Communities and Community Lists Overview 433

ip community-list 433

ip community-set 434

BGP Communities and Community Lists Overview

BGP updates carry a number of path attributes. Some of these, like the AS_PATH, are mandatory and

appear in every update message sent. Others are optional, and may or may not appear in any given update. Of the optional attributes, two can be specified arbitrarily by administrators to ease configuration. These two attributes are "communities" and "extended communities." Both of these attributes operate by "coloring" routes received in updates where these attributes are present; every router keeps track of the set of communities and extended communities with which a route was learned. The particular communities (or extended communities) with which a route was learned can be used to indicate that a particular set of policies should be applied to those routes.

ip community-list

Name

ip community-list - specifies a community or group of communities used in filtering or modifying

community values

Syntax

ip community-list name [permit | deny] [comm-set commset_name] [exact]? [standard | extended]?

no ip community-list name [permit | deny] [comm-set commset_name] [exact]? [standard | extended]?

Mode

Global Configuration

Parameters

name - a string of characters that uniquely identifies this community list

permit | deny - permits or denies the entries in the community list. When creating a community list, by

default, the end of the community list contains an implicit deny statement for everything.

comm-set commset_name - specify a community set or an extended community set

ip community-set

BGP Communities and Community Lists Page 434

exact - optionally specify whether an entire community list must be matched exactly

standard - specifies that the referenced community set is a standard (non-extended) community set.

standard and extended are mutually exclusive. Note: If neither standard nor extended is specified for

a standard community list, then the default value is standard. If both are configured, the keyword supplied

last will override the previous.

extended - specifies that the referenced community set is an extended (non-standard) community set.

standard and extended are mutually exclusive. If both are configured, the keyword supplied last will

override the previous.

Description

The ip community-list command is used to specify a community, an extended community, or groups of

both used in filtering or modifying community values. Multiple community lists for the same name can be specified to create multiple elements in the list. This list is generated in the order in which the commands are entered.

Default

Community lists are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a community list with two list entries. The first entry permits a community set labeled set1, and the second entry permits a community set labeled set2. Note that set1 and set2 are implicitly taken to refer to the names in the standard community set name space.

(config)# ip community-set set1 101:101

(config)# ip community-set set2 101:104

(config)# ip community-list abc permit comm-set set1 exact

(config)# ip community-list abc permit comm-set set2 exact

Example 2

The following example configures a community set, "set1", that includes AS:num 101:102. It then configures an extended community set "ext-set1", that includes Route Target AS:num 201:202. The two are then added to an extended community list, called "commlist1".

(config)# ip community-set set1 101:102

(config)# ip community-set ext-set1 extended rt 201:202

(config)# ip community-list commlist1 permit comm-set set1 extended

(config)# ip community-list commlist1 permit comm-set ext-set1 extended

ip community-set

Name

ip community-set - specifies a community or group of communities or extended communities used in

filtering or modifying community values

ip community-set

BGP Communities and Community Lists Page 435

Syntax

Standard BGP Communities

ip community-set set_id [as:num | comm-num | local-as | no-advertise | no-export | none ] {1,n}

no ip community-set set_id [as:num | comm-num | local-as | no-advertise | no-export | none ] {1,n}

Extended BGP Communities

ip community-set set_id extended [ none | (rt [as:num | ip:num]) | (rt4 [as:num | ip:num]) | (soo [as:num | ip:num]) | (soo4 [as:num | ip:num]) | (lbw as:float) (*:*) ] {1,n}

no ip community-set set_id extended [ none | (rt [as:num | ip:num]) | (soo [as:num | ip:num]) | (lbw as:float) (*:*) ] {1,n}

Mode

Global Configuration

Parameters

Standard BGP Communities

set_id - a string of characters that uniquely identifies this community set

as:num - the autonomous system (AS) number to be concatenated with a number specified as a 16-bit

number. This is used for specifying a community in the "community-split" style.

comm-num - the concatenation value of the two sixteen-bit numbers used for this arbitrary community

local-as - specifies the well-known community NO_EXPORT_SUBCONFED as defined in RFC 1997.

Routes tagged with this community are not to be advertised to external peers, including those peers in other members’ autonomous systems inside of a BGP confederation.

no-advertise - specifies the well-known community NO_ADVERTISE as defined in RFC 1997. Routes

tagged with this community are not to be advertised to any other peers.

no-export - specifies the well-known community NO_EXPORT as defined in RFC 1997. Routes tagged

with this community are not to be exported outside of a confederation boundary when confederations are in use or if they are outside of the local AS when confederations are not configured.

none - specifies the empty set of communities. It is useful only where matches are being attempted. When

used in that context, if a route has any communities associated with it, then it does not match; otherwise, it does match. Note: Empty sets of communities cannot be combined with other communities in the list.

{1,n} - this command must be used at least once, and can be used an unlimited number of times for a

single community set ID

Extended BGP Communities

set_id - a string of characters that uniquely identifies this community set

none - specifies the empty set of extended communities. Note: Empty sets of extended communities

cannot be combined with other communities in the list.

rt (as:num | ip:num) - specifies the Route Target extended community. This is followed by either the

autonomous system (AS) number to be concatenated with num (specified as a 32-bit number), or an IPv4 address in dotted-quad format with a 16-bit number value for num.

rt4 (as:num | ip:num) - specifies a 4-bit Route Target extended community. This is followed by either

the autonomous system (AS) number to be concatenated with num (specified as a 2-bit number), or an IPv4 address in dotted-quad format with a 16-bit number value for num.

soo (as:num | ip:num) - specifies the Site of Origin (Route Origin) extended community. This is

followed by either the autonomous system (AS) number to be concatenated with num (specified as a 32-bit number), or an IPv4 address in dotted-quad format with a 16-bit number value for num.

ip community-set

BGP Communities and Community Lists Page 436

soo4 (as:num | ip:num) - specifies the Site of Origin (Route Origin) extended community. This is

followed by either the 4-bit autonomous system (AS) number to be concatenated with num (specified as a 2-bit number), or an IPv4 address in dotted-quad format with a 16-bit number value for num.

lbw as:float - specifies the Link Bandwidth extended community. This is followed by the autonomous

system number and floating point numbering expressing the speed of a link in bytes per second.

*:* - specifies all extended communities

{1,n} - this command must be used at least once, and can be used an unlimited number of times for a

single extended community ID

Description

The ip community-set command is used to specify a set of communities and extended communities that

must be matched for a route to be considered a match.

BGP updates carry a number of path attributes. Some of these, like the s, are mandatory and appear in

every update message sent. Others are optional, and may or may not appear in any given update. Of the optional attributes, two can be specified arbitrarily by administrators to ease configuration. These two attributes are "communities" and "extended communities." Both of these attributes operate by "coloring" routes received in updates where these attributes are present; every router keeps track of the set of communities and extended communities with which a route was learned. The particular communities (or extended communities) with which a route was learned can be used to indicate that a particular set of policies should be applied to those routes.

Notes:

You cannot mix standard and extended communities in the same community set.

If you configure a community set twice, the second configuration overwrites the first. The two configurations will not merge.

Separate name spaces are used for standard and extended community sets. Thus, the same set name can be used for both a standard and an extended community set.

Default

Community sets are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a community set named "abc" that includes AS:num 201:202.

(config)# ip community-set abc permit 201:202

Example 2

The following example configures an extended community set "ext-set1", with a Route Target AS:num 201:202 and a site of origin IP number 10.1.2.3:100.

(config)# ip community-set ext-set1 extended rt 201:202 soo 10.1.2.3:100

Page 437

Chapter 23

Prefix Lists and Prefix Trees

In This Chapter

Prefix Lists and Prefix Trees Overview 437

ip prefix-list 437

ip prefix-list sequence-number 438

ip prefix-tree 439

show ip prefix-list 441

show ip prefix-tree 442

Prefix Lists and Prefix Trees Overview Advanced Routing Suite provides two types of prefix based lists; Prefix Lists and Prefix Trees. Prefix Trees return the longest match as the true match whereas Prefix Lists simulate a sequential lookup and return the first matched entry as the true match. The entries are ordered according to entry-seq.

ip prefix-list

Name

ip prefix-list - creates a prefix list

Syntax

ip prefix-list list_id [seq seq_value]? [deny | permit] [network/masklen] [ge length]? [le length]?

no ip prefix-list list_id [seq seq_value]? [deny | permit] [network/masklen] [ge length]? [le length]?

Mode

Global Configuration

Parameters

list_id - a string of characters or an integer

seq seq_value - this is specified as an integer between 0 and 4,294,967,295, inclusive. Note: Sequence

numbers are generated automatically in increments of 5 unless automatic generation is turned off. If automatic generation is disabled, then the sequence number must be specified. Otherwise, specifying this command is optional.

deny | permit - denies or permits the specified source address

network/masklen - specify a valid IPv4 address with a mask length. The IPv4 address is specified in

dotted-quad format; the mask length is an integer from 0 to 32, inclusive. Note that the "/" is required.

ge length - specifies that the IPv4 address matches (prefix, mask) pairs with exactly the same prefix

address and mask lengths that are greater than or equal to the value of the ge command. This value can be

in the range of 0 to 32, but it must be at least the value of masklen and no greater than the value of le.

ip prefix-list sequence-number

Prefix Lists and Prefix Trees Page 438

le length - specifies that the IPv4 address matches (prefix, mask) pairs with exactly the same prefix

address and mask lengths that are less than or equal to the value of the le command. This value can be in

the range of 0 to 32, but it must be at least the value of masklen and no less than the value of ge.

Description

Prefix lists simulate a sequential lookup and return the first matched entry as the true match. The entries are ordered according to the sequential value. Sequence numbers are generated automatically unless automatic generation is disabled. If the automatic generation of sequence numbers is disabled, then the sequence number for each entry must be specified.

The optional ge and le commands can be used to specify the range of the prefix length to be matched for

prefixes that are more specific than a network and netmask value. If only the gelength is specified, then the

range is assumed to be from gelength to 32. If only the lelength is specified, then the range is assumed to

be less than the lelength. An exact match is assumed when neither ge nor le is specified.

Use the negative form of this command to delete all entries or specific entries in a prefix list. One way to remove a specific entry from a prefix list is to specify all parameters that were specified when the entry was created. Another way is to specify the sequence number of the entry, which is either automatically generated or explicitly configured.

Default

Prefix lists are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a prefix list "abc" that denies all prefixes in 128.0.0.0/8 with a prefix length of 24.

(config)# ip prefix-list abc deny 128.0.0.0/8 ge 24 le 24

Example 2

The following example configures a prefix list "abc" with three list entries. The first and second entries permit all routes matching 10.0.0.0 with prefix length equal to 8 (first entry) except 10.1.1.1 (second entry). The third entry permits all other IPv4 routes. An implicit deny is assumed for all other routes.

(config)# ip prefix-list abc permit 10.0.0.0/8 ge 8 le8

(config)# ip prefix-list abc deny 10.1.1.1/32 ge 32 le 32

(config)# ip prefix-list abc permit 0.0.0.0/0 le 32

ip prefix-list sequence-number

Name

ip prefix-list sequence-number - specifies whether Advanced Routing Suite should use automatic

sequence numbering when configuring prefix lists

Syntax

ip prefix-list sequence-number

no ip prefix-list sequence-number

Mode

Global Configuration

ip prefix-tree

Prefix Lists and Prefix Trees Page 439

Parameters

none

Description

Sequence values are generated in increments of 5, with the first sequence value generated being 5, then 10, then 15, and so on. If a sequence value is specified for an entry, and then not specified for subsequent entries, the assigned (generated) sequence values are then incremented in units of 5 based on the highest sequence number present in the list.

Note: Sequence numbers are generated automatically in increments of 5 unless automatic generation is turned off. If automatic generation is disabled, then the sequence number must be specified. Otherwise,

specifying this command is optional. Use the negative form of the sequence command, no ip

prefix-list sequence-number, to turn off automatic sequence number generation.

Default

Sequence numbers are generated automatically by Advanced Routing Suite. Therefore, if ip

prefix-list sequence-number is not specified, it is the same as if the user had specified the following:

(config)# ip prefix-list sequence-number

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures four entries in prefix list "abc." The first entry explicitly configures sequence number 3. The two subsequent entries will, therefore, have automatically generated sequence numbers of 8 and 13 respectively. Sequence numbering is then turned off, and the fourth entry is configured

with a sequence number of 20. The show ip prefix-list query that follows displays the prefix list entries

with their sequence numbers.

(config)# ip prefix-list abc seq 3 permit 10.11.0.0/16 ge 20 le 20

(config)# ip prefix-list abc deny 10.10.0.0/16 ge 24 le 28

(config)# ip prefix-list abc permit 12.12.0.0 16

(config)# no ip prefix-list sequence-number

(config)# ip prefix-list abc seq 20 permit 192.168.0.0/16

(config)# exit

# show ip prefix-list abc

ip prefix-list abc: 4 entries seq 3 permit 10.11.0.0/16 ge 20 le 20 seq 8 deny 10.10.0.0/16 ge 24 le 28 seq 13 permit 12.12.0.0/16 seq 20 permit 192.168.0.0/16

#

ip prefix-tree

Name

ip prefix-tree - configures a prefix tree

Syntax

ip prefix-tree tree_id [deny | permit] [network/masklen] [ge length]? [le length]?

ip prefix-tree

Prefix Lists and Prefix Trees Page 440

no ip prefix-tree list_id [deny | permit] [network/masklen] [ge length]? [le length]?

Mode

Global Configuration

Parameters

tree_id - a string of characters

deny | permit - denies or permits the specified source address

network/masklen - specify a valid IPv4 address with a mask length. The IPv4 address is specified in

dotted-quad format; the mask length is an integer from 0 to 32, inclusive. Note that the "/" is required.

ge length - specifies that the IPv4 address matches (prefix, mask) pairs with exactly the same prefix

address and mask lengths that are greater than or equal to the value of the ge command. This value can be

in the range of 0 to 32, but it must be at least the value of masklen and no greater than the value of le.

le length - specifies that the IPv4 address matches (prefix, mask) pairs with exactly the same prefix

address and mask lengths that are less than or equal to the value of the le command. This value can be in

the range of 0 to 32, but it must be at least the value of masklen and no less than the value of ge.

Description

Prefix Trees return the longest match as the true match whereas Prefix Lists simulate a sequential lookup and return the first matched entry as the true match.

The optional ge and le commands can be used to specify the range of the prefix length to be matched for

prefixes that are more specific than a network and netmask value. If only the gelength is specified, then the

range is assumed to be from gelength to 32. If only the lelength is specified, then the range is assumed to

be less than the lelength.

Use the negative form of this command to delete all entries or specific entries in a prefix tree. You can remove a specific entry from a prefix tree by specifying all parameters that were specified when the entry was created.

Default

Prefix trees are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following example configures a prefix tree "abc" that denies all prefixes in 128.0.0.0/8 with a prefix length of 24.

(config)# ip prefix-tree abc deny 128.0.0.0/8 ge 24 le 24

Example 2

The following example configures a prefix tree "abc" with three list entries. The first and second entries permit all routes matching 10.0.0.0 with prefix length equal to 8 (first entry) except 10.1.1.1 (second entry). The third entry permits all other IPv4 routes. An implicit deny is assumed for all other routes.

(config)# ip prefix-tree abc permit 10.0.0.0/8 ge 8 le8

(config)# ip prefix-tree abc deny 10.1.1.1/32 ge 32 le 32

(config)# ip prefix-tree abc permit 0.0.0.0/0 le 32

show ip prefix-list

Prefix Lists and Prefix Trees Page 441

show ip prefix-list

Name

show ip prefix-list - displays information about all or specific prefix lists

Syntax

show ip prefix-list [ detail | summary ]? [ list_id ]?

Mode

Privileged Execution

Parameters

detail | summary - optionally specify whether you want the query to respond with a more verbose

format. Summary information is returned by default.

list_id - a string of characters or an integer that represents the ID of a configured prefix list. Specifying this

is optional. Advanced Routing Suite will return information for all configured IPv4 prefix lists if a list_id is

not specified.

Description

The show ip prefix-list query displays information about all or specific prefix lists.

This query has two forms. If it is issued without arguments, then information about all configured IPv4 prefix lists is returned. Alternatively, the query can be issued naming a specific prefix list. In this case, the reply will contain information pertaining only to the referenced prefix list.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following query is a request for summary information about a prefix list named "pfxtest1".

# show ip prefix-list pfxtest1

ip prefix-list pfxtest1: 3 entries seq 3 deny 10.10.0.0/16 ge 20 le 20 seq 8 permit 10.10.0.0/16 ge 24 le 28 seq 13 permit 12.12.0.0/16

Example 2

The following query is a request for summary information about all configured IPv4 prefix lists.

# show ip prefix-list

ip prefix-list pfxtest1: 3 entries seq 3 deny 10.10.0.0/16 ge 20 le 20 seq 8 permit 10.10.0.0/16 ge 24 le 28 seq 13 permit 12.12.0.0/16

ip prefix-list pfxtest2: 4 entries seq 3 permit 10.2.2.2/24 ge 24 le 24 seq 8 deny 10.1.1.1/32 ge 32 le 32 seq 10 permit 10.0.0.0/8 ge 8 le 8 seq 11 permit 0.0.0.0/8 le 8

Example 3

The following is a request for detail information about a prefix list named "pfxtest2".

show ip prefix-tree

Prefix Lists and Prefix Trees Page 442

# show ip prefix-list detail pfxtest2

ip prefix-list pfxtest2: count: 4, sequences 3 - 11 seq 3 permit 10.2.2.2/24 ge 24 le 24 seq 8 deny 10.1.1.1/32 ge 32 le 32 seq 10 permit 10.0.0.0/8 ge 8 le 8 seq 11 permit 0.0.0.0/8 le 8

show ip prefix-tree

Name

show ip prefix-tree - displays information about all or specific prefix trees

Syntax

show ip prefix-tree [ detail | summary ]? [ tree_id ]?

Mode

Privileged Execution

Parameters

detail | summary - optionally specify whether you want the query to respond with a more verbose

format. Summary information is returned by default.

tree_id - a string of characters or an integer that represents the ID of a configured prefix tree. Specifying

this is optional. Advanced Routing Suite will return information for all configured IPv4 prefix trees if a

tree_id is not specified.

Description

The show ip prefix-tree query displays information about all or specific prefix trees.

This query has two forms. If it is issued without arguments, then summary information about all configured IPv4 prefix trees is returned. Alternatively, the query can be issued naming a specific prefix tree. In this case, the reply will contain information pertaining only to the referenced prefix tree.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

The following query is a request for summary information about a prefix tree named "pfxtest1".

# show ip prefix-tree pfxtest1

ip prefix-tree abc: 1 entries deny 128.0.0.0 0.255.255.255 ge 24 le 24

Example 2

The following query is a request for summary information about all configured IPv4 prefix trees.

# show ip prefix-tree

ip prefix-tree pfxtest1: 3 entries deny 10.10.0.0 0.0.255.255 ge 20 le 20 permit 10.10.0.0 0.0.255.255 ge 24 le 28 permit 12.12.0.0 0.0.255.255

show ip prefix-tree

Prefix Lists and Prefix Trees Page 443

ip prefix-tree pfxtest2: 4 entries permit 10.2.2.2 0.255.255.255 ge 24 le 24 deny 10.1.1.1 255.255.255.255 ge 32 le 32 permit 10.0.0.0 0.0.0.255 ge 8 le 8 permit 0.0.0.0 0.0.0.255 le 8

Example 3

The following is a request for detail information about a prefix tree named "pfxtest2".

# show ip prefix-tree detail pfxtest2

ip prefix-tree pfxtest2: count: 4, sequences 3 - 11 permit 10.2.2.2 0.255.255.255 ge 24 le 24 deny 10.1.1.1 255.255.255.255 ge 32 le 32 permit 10.0.0.0 0.0.0.255 ge 8 le 8 permit 0.0.0.0 0.0.0.255 le 8

Page 444

Chapter 24

Route Aggregation and Generation

In This Chapter

Route Aggregation and Generation Overview 444

aggregate-address 444

router aggregate 448

Route Aggregation and Generation Overview

Route aggregation is a method of generating a more general summary route, given the presence of a more specific route. It is used, for example, at an autonomous system border to generate a route to a network to be advertised via BGP, given the presence of one or more subnets of that network learned via RIP. No aggregation is performed unless explicitly requested in an aggregate command.

Route aggregation is also used by regional and national networks to reduce the amount of routing information passed. With careful allocation of network addresses to clients, regional networks can announce one route to regional networks instead of hundreds.

Aggregate routes are not actually used for packet forwarding by the originator of the aggregate route, only by the receiver (if it wishes). A router is supposed to respond with an ICMP network unreachable message if the router receives a packet that does not match one of the component routes that led to the generation of an aggregate route. This message is to prevent packets for unknown component routes from following a default route into another network, where they would be forwarded back to the border router, and around and around again and again, until their TTL expired. Sending an unreachable message for a missing piece of an aggregate is only possible on systems with support for reject routes.

A difference between route aggregation and generation is the generation of a route based on the existence of certain conditions. This is sometimes known as the "route of last resort." This route inherits the next hops and AS path from the contributor specified with the lowest (most favorable) preference. The most common usage for this is to generate a default based on the presence of a route from a peer on a neighboring backbone.

aggregate-address

Named

aggregate-address - allows the aggregation of specific routes into one

Syntax

aggregate-address [(address (mask | masklen)?) | prefix ] protocol [aggregate | all | bgp | direct | kernel | ospf |

rip | ripng | static] [match-map map_name]? (rib [unicast | multicast | unicast-multicast])? [preference pref]? generate? noinstall? blackhole? bgp? brief?

no aggregate-address [(address (mask | masklen)?) | prefix ] protocol [aggregate | all | bgp | direct |

aggregate-address

Route Aggregation and Generation Page 445

isis | kernel | ospf | rip | ripng | static] [match-map map_name]? (rib [unicast | multicast | unicast-multicast])? [preference pref]? generate? noinstall? blackhole? bgp? brief?

Mode

Aggregate Router Configuration Mode

Parameters

address (mask | masklen) - the IPv4 address to be aggregated or generated. Specify either an address

or a prefix. The address can be accompanied by an address mask or masklen. The address mask is

specified in dotted-quad format for IPv4 addresses. The masklen specifies the number of contiguous bits at

the beginning of a mask.

prefix - specifies a valid IPv4 prefix

protocol - specify the protocol whose rules this aggregate will use to determine whether to include each

route. For IPv4 routes, valid values include the following: aggregate, all, bgp, direct, kernel, ospf,

rip, and static.

match-map map_name - optionally specify a route map that will be used to generate this route

rib [ unicast | multicast | unicast-multicast ] - specifies whether the aggregate is restricted

to the unicast RIB, the multicast RIB, or both. The default is to restrict the aggregate to both the unicast and multicast RIB.

brief - specifies that the AS path should be truncated to the longest common leading AS path. This is

option is only useful if the configured protocol is BGP.

bgp - specifies that this aggregate will use BGP rules to determine whether to include each route. This is a

valid option only if the configured protocol is BGP.

preference pref - specifies the aggregation preference value to be assigned to the contributor route.

This can be an integer between 1 and 255, inclusive. Note: If two different aggregate commands are specified for the same prefix, then the preference specified most recently will be used by Advanced Routing

Suite, and that preference value will display in the show running-config query for each configured

aggregate route.

noinstall - specifies whether to install the generate address if any contributor route is active. The default

behavior is to install the route.

generate - generates a default route. Route generation is a method of generating a more general route,

given the presence of a specific route. generate differs from aggregate only in terms of the route

installed in the kernel.

blackhole - specifies whether to blackhole the route; thus enabling the router to refuse to route various

prefixes

Description

Route aggregation is a method of generating a more general summary route, given the presence of a more

specific route. generate differs from aggregate only in terms of the route installed in the kernel.

Note: Using the generate keyword in the no form restores the default for the generate route but has no

effect on the aggregate route. To restore the default for the aggregate route, use the no form of the

command without the generate keyword. This will have a cascading effect on restoring the default

generated route.

Default

No aggregate/generate routes are configured by default.

Command History

NGC 2.2 - This command was introduced.

aggregate-address

Route Aggregation and Generation Page 446

Examples

Example 1

In the following example, an aggregate route to 10/8 is generated based on routes formed via BGP that match route map "rm1".

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol bgp match-map rm1

(config-aggregate)# exit

(config)#

Example 2

The following example removes the configuration in Example 1 and restores the defaults.

(config)# router aggregate

(config-aggregate)# no aggregate-address 10.0.0.0 255.0.0.0 protocol bgp

(config-aggregate)# exit

(config)#

Example 3

In the following example, a generate route to 10/8 is created based on routes formed via BGP that match route map "rm1".

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol bgp match-map rm1 generate

(config-aggregate)# exit

(config)#

Example 4

The following example removes the configuration in Example 3 and restores the defaults.

(config)# router aggregate

(config-aggregate)# no aggregate-address 10.0.0.0 255.0.0.0 protocol bgp generate

(config-aggregate)# exit

(config)#

Example 5

The following example creates an aggregate route that includes all OSPF routes matching route map "rm1" and that are more specific than 10/8. It also restricts it to the unicast RIB.

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol ospf match-map rm1 rib unicast

(config-aggregate)# exit

(config)#

Example 6

The following example creates a generate route from all OSPF routes that match route map "rm1" and that are more specific than 10/0. It restricts the generate route to the unicast RIB. The routes, however, will not be installed if the contributor route is not active.

aggregate-address

Route Aggregation and Generation Page 447

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol ospf

match-map rm1 rib unicast generate noinstall

(config-aggregate)# exit

(config)#

Example 7

The following example restores the defaults in Example 6.

(config)# router aggregate

(config-aggregate)# no aggregate-address 10.0.0.0 255.0.0.0 protocol ospf rib unicast generate

(config-aggregate)# exit

(config)#

Example 8

The following example creates an aggregate route that includes all ISIS routes matching route map "rm1" and that are more specific than 10/8. In addition, it sets the preference for these routes to 10.

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol isis match-map rm1 preference 10

(config-aggregate)# exit

(config)#

Example 9

The following example creates an aggregate route that includes all RIP routes matching route map "rm1" and that are more specific than 10/8. It also sets the preference for the aggregate route to 10.

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol rip match-map rm1 preference 10

(config-aggregate)# exit

(config)#

Example 10

The following example creates a generate route from all RIP routes matching route map "rm1" and that are more specific than 10/8. It also sets the preference for these routes to 10. The routes, however, will not be installed if the contributor route is not active.

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol rip match-map rm1 preference 10 generate noinstall

(config-aggregate)# exit

(config)#

Example 11

The following example creates an aggregate route that includes all static routes matching route map "rm1" and that are more specific than 10/8. IT also sets the preference for the aggregate route to 10.

(config)# router-aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol static match-map rm1 preference 10

(config-aggregate)# exit

router aggregate

Route Aggregation and Generation Page 448

(config)#

Example 12

The following example creates a generate route from all static routes that match route map "rm1" and that are more specific than 10/8. It also sets the preference for these routes to 10.

(config)# router aggregate

(config-aggregate)# aggregate-address 10.0.0.0 255.0.0.0 protocol static match-map rm1 preference 10 generate

(config-aggregate)# exit

(config)#

router aggregate

Name

router aggregate - enters the user into Aggregate Router Configuration mode

Syntax

router aggregate

Mode

Global Configuration

Parameters

none

Description

Use the router aggregate command to enter Aggregate Router Configuration mode. This mode allows the aggregation of specific routes into a single route.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example shows how to enter Aggregate Router Configuration mode.

(config)# router aggregate

(config-aggregate)#

Page 449

Chapter 25

Route Flap Damping

In This Chapter

Route Flap Damping Overview 449

dampen-flap 449

keep-history 450

max-flap 451

reach-decay 451

reach-tick 452

reuse-below 453

suppress-above 454

unreach-decay 454

Route Flap Damping Overview Weighted route dampening treats routes that are being announced and withdrawn (flapping) at a rapid rate as unreachable. If a route flaps at a low rate, it should not be suppressed at all, or suppressed for only a brief period of time. With weighted route dampening, the suppression of a route or routes occurs in a manner that adapts to the frequency and duration that a particular route appears to be flapping. The more a route flaps during a period of time, the longer it will be suppressed. The adaptive characteristics of weighted route dampening are controlled by a few tags.

Note: Route flap damping currently only applies to BGP.

dampen-flap

Name

dampen-flap - enters the user into Dampen Flap Configuration mode

Syntax

dampen-flap name

no dampen-flap name

Mode

Global Configuration

Parameters

name - a string of characters uniquely identifying a dampen-flap configuration

Description

The dampen-flap command enters the user into Dampen Flap Configuration mode, where

route-flap-damping parameters can be specified. The negative form of this command, no dampen-flap,

removes the configured damping.

keep-history

Route Flap Damping Page 450

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures route flap damping with an ID of rfd1.

(config)# dampen-flap rfd1

(config-dampen-flap)#

keep-history

Name

keep-history - specifies the time in seconds for which any history of a route's instability is maintained

Syntax

keep-history time-seconds

no keep-history time-seconds?

Mode

Dampen Flap Configuration

Parameters

time-seconds - specifies a time in seconds from 1 to 604800, inclusive

Description

The keep-history command specifies time in seconds for which any history of a route’s instability is

maintained. The negative form of this command, no keep-history, removes the configured value and

returns this to its default value of 1800 seconds. Note: Specifying a value for time-seconds in the no form

has no effect on the configuration. Thus, it is displayed above as optional.

Default

If keep-history is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# keep-history 1800

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the keep-history value to be 2000 seconds.

(config)# dampen-flap rfd1

(config-dampen-flap)# keep-history 2000

max-flap

Route Flap Damping Page 451

max-flap

Name

max-flap - specifies the maximum value of a route’s instability history

Syntax

max-flap float

no max-flap float?

Mode

Dampen Flap Configuration

Parameters

float - an integer or floating point number between 2.1 and 604800, inclusive

Description

Use the max-flap command to specify the maximum value of a route’s instability history. The instability

metric is incremented by 1 each time a route becomes unreachable. The max-flap value, which must be greater than the suppress-above value, determines the longest time that a route can be suppressed.

The negative form of this command, no max-flap, removes the configured value and returns this to its

default value of 16.0. Note: Specifying a value for float in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If max-flap is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# max-flap 16.0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the maximum value of the route’s instability history to be 18.

(config)# dampen-flap rfd1

(config-dampen-flap)# max-flap 18

See Also

"suppress-above" ("suppress-above" on page 454)

reach-decay

Name

reach-decay - specifies the time in seconds after which a reachable route’s instability history decays to

half of its current value

Syntax

reach-decay time-seconds

no reach-decay time-seconds?

reach-tick

Route Flap Damping Page 452

Mode

Dampen Flap Configuration

Parameters

time-seconds - specifies a time in seconds from 1 to 604800, inclusive

Description

Use the reach-decay command to specify a time in seconds, after which a reachable route’s instability

history decays to half of its current value. The negative form of this command, no reach-decay, removes

the configured value and returns this to its default value of 300 seconds. Note: Specifying a value for

time-seconds in the no form has no effect on the configuration. Thus, it is displayed above as optional.

Default

If reach-decay is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# reach-decay 300

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the reach-decay value to be 600 seconds.

(config)# dampen-flap rfd1

(config-dampen-flap)# reach-decay 600

reach-tick

Name

reach-tick - specifies the granularity of instability history in seconds

Syntax

reach-tick time-seconds

no reach-tick time-seconds?

Mode

Dampen Flap Configuration

Parameters

time-seconds - an integer between 1 and 604800, inclusive, used to specify the time in seconds

Description

The reach-tick command specifies the granularity of instability history in seconds. The negative form of

this command, no reach-tick, removes the configured value and returns this to its default value of 1

second. Note: Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it

is displayed above as optional.

Default

If reach-tick is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# reach-tick 1

reuse-below

Route Flap Damping Page 453

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the reach-tick value to be 5 seconds

(config)# dampen-flap rfd1

(config-dampen-flap)# reach-tick 5

reuse-below

Name

reuse-below - specifies the value of a route’s instability, below which a suppressed route is reused

Syntax

reuse-below float

no reuse-below float?

Mode

Dampen Flap Configuration

Parameters

float - a floating point number whose value is less than or equal to the suppress-above value, and in the

range of 1.0 to 604800, inclusive

Description

The reuse-below command specifies the value of a route’s instability metric, below which a suppressed

route is reused. The value for this command must be less or equal to the suppress-above value.

The negative form of this command, no reuse-below, removes the configured value and returns this to its

default value of 1.0. Note: Specifying a value for float in the no form has no effect on the configuration.

Thus, it is displayed above as optional.

Default

If reuse-below is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# reuse-below 1.0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the reuse-below value to be 6

(config)# dampen-flap rfd1

(config-dampen-flap)# reuse-below 6

See Also

"suppress-above" ("suppress-above" on page 454)

suppress-above

Route Flap Damping Page 454

suppress-above

Name

suppress-above - specifies the value of a route’s instability, above which the route is suppressed

Syntax

suppress-above float

no suppress-above float?

Mode

Dampen Flap Configuration

Parameters

float - a floating point number whose value is greater than or equal to the reuse-above value, and in the

range of 2.0 to 604800, inclusive

Description

The suppress-above command specifies the value of a route’s instability metric, above which the route is

suppressed. The negative form of this command, no suppress-above, removes the configured value and

returns this to its default value of 2.0. Note: Specifying a value for float in the no form has no effect on the

configuration. Thus, it is displayed above as optional.

Default

If suppress-above is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# suppress-above 2.0

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the suppress-above value to be 8.

(config)# dampen-flap rfd1

(config-dampen-flap)# suppress-above 8

See Also

"reuse-below" ("reuse-below" on page 453)

unreach-decay

Name

unreach-decay - specifies the time in seconds after which an unreachable route’s instability history

decays to half its current value

Syntax

unreach-decay time-seconds

no unreach-decay time-seconds?

unreach-decay

Route Flap Damping Page 455

Mode

Dampen Flap Configuration

Parameters

time-seconds - specifies a time in seconds from 1 to 604800, inclusive

Description

Use the unreach-decay command to specify a time in seconds, after which a unreachable route’s

instability history decays to half of its current value. The negative form of this command, no

unreach-decay, removes the configured value and returns this to its default value of 900 seconds. Note:

Specifying a value for time-seconds in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

Default

If unreach-decay is not specified, it is the same as if the user had specified the following:

(config-dampen-flap)# unreach-decay 900

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures the unreach-decay value to be 600 seconds.

(config)# dampen-flap rfd1

(config-dampen-flap)# unreach-decay 600

Page 456

Chapter 26

Route Maps

In This Chapter

Route Maps Overview 457

match aggregate-contributors 457

match as 458

match as-path 458

match as-path-list 459

match community 460

match community-set 461

match distance 462

match extended-community-set 463

match instance 464

match interface 465

match ip address access-list 466

match ip address prefix-list 466

match ip address prefix-tree 467

match ip gateway 468

match ip next-hop 469

match ip route-source prefix-tree 470

match localpref 471

match med 471

match metric 472

match metric-type 473

match protocol 473

match ribs 474

match tag 475

route-map 476

set as-path prepend 477

set community-set 478

set dampen-flap 479

set ip next-hop 479

set local-preference 480

set med 481

set metric 482

set metric-type 482

set origin 483

set preference 484

set propagate 485

set ribs 486

set tag 486

Route Maps Overview

Route Maps Page 457

Route Maps Overview Route maps can be used to filter learned routes or to redistribute routes between protocols. Route map commands specify match and set criteria associated with the route map.

match aggregate-contributors

Name

match aggregate-contributors - specifies that in order for a route to match, it must be a contributor

to an aggregate route

Syntax

match aggregate-contributors [invert]?

no match aggregate-contributors [invert]?

Mode

Route Map Configuration

Parameters

invert - optionally specify to reverse the result of a match

Description

Use the match aggregate-contributors command to specifies that, in order for a route to match, it

must be a contributor to an aggregate route.

Default

This command is configured by default. Therefore, if match aggregate-contributors is not specified, it

is the same as if the user had specified the following:

(config-route-map)# match aggregate-contributors

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being matched is an aggregate contributor and has an AS_PATH matching the AS path list labeled "list1", then the following set actions will be executed:

Communities specified in community "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2 will be deleted from the matching route.

The metric for the matching routes will be set to 1.

(config)# route-map abc

(config-route-map)# match aggregate-contributors

(config-route-map)# match as-path-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 1

(config-route-map)# exit

(config)#

match as

Route Maps Page 458

match as

Name

match as - filters BGP routes learned from peers within a particular autonomous system (AS)

Syntax

match as as_number [invert]?

no match as as_number [invert]?

Mode

Route Map Configuration

Parameters

as_number - an integer between 1 and 65535, inclusive, specifying the number of an AS

invert - optionally specify to reverse the result of a match

Description

Use the match as command to filter BGP routes learned from peers within a particular autonomous system.

Note: This command applies only to BGP routes. It will be ignored for any other protocol.

Default

AS matching policy is not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures route map "matchbgp" and specifies to match BGP routes learned from peers within AS 65535.

(config)# route map matchbgp

(config-route-map)# match as 65535

(config-route-map)# exit

(config)#

match as-path

Name

match as-path - specifies the name of the AS Path Regular Expression to be matched

Syntax

match as-path name [invert]?

no match as-path name [invert]?

Mode

Router Map Configuration

match as-path-list

Route Maps Page 459

Parameters

name - the name of the AS Path Regular Expression to be matched

invert - optionally specify to reverse the result of a match

Description

Use the match as-path command to specify a pre-configured AS Path Regular Expression that you want

to be matched in this route map. If the referenced AS Path Regular Expression has not yet been configured, then the result is that the match fails.

Note: This command applies only to BGP routes. It will be ignored for all other protocols.

Default

No AS Path matches are configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being evaluated against route map "abc" matches interface "fxp1" and the AS path regular expression "aspath1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The metric for the matching route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match as-path aspath1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

match as-path-list

Name

match as-path-list - specifies a pre-configured AS Path list to be matched

Syntax

match as-path-list name [invert]?

no match as-path-list name [invert]?

Mode

Route Map Configuration

Parameters

name - the name of a pre-configured AS Path list

invert - optionally specify to reverse the result of a match

match community

Route Maps Page 460

Description

Use the match as-path-list command to specify a pre-configured AS Path list that you want to be

matched in this route map. If the referenced AS Path list has not yet been configured, then the result is that the match fails.

Note: This command applies only to BGP routes. It will be ignored for all other protocols.

Default

No AS Path lists are matched by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being evaluated against route map "abc" matches interface "fxp1" and the AS path list labeled "list1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The metric for the matching route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match as-path-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

match community

Name

match community - specifies a BGP community list to be matched in a route map

Syntax

match community name [invert]?

no match community name [invert]?

Mode

Route Map Configuration

Parameters

name - the name of a BGP community list

invert - optionally specify to reverse the result of a match

Description

Use the match community command to specify a BGP community list that you want to be matched in this

route map. If the referenced community list has not yet been configured, then the result is that the match fails.

match community-set

Route Maps Page 461

Note: This command applies only to BGP routes. It will be ignored for all other protocols.

Default

No BGP community lists are matched by default.

Command History

NGC 2.2 - This command was introduced.

Examples

Example 1

In the following example, if the route being evaluated against route map "abc" matches the BGP Community List "commlist1" and the AS path list labeled "aspathlist1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The metric for the matching route will be set to 50.

(config)# route-map abc

(config-route-map)# match community commlist1

(config-route-map)# match as-path-list aspathlist1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

Example 2

The following example configures route map "abc". If a route being evaluated against this route map does not match community list "comm-list-1", then communities specified in the community set "comm-set-1" will be deleted from the route, and the route will be considered to have matched.

(config)# route-map abc

(config-route-map)# match community comm-list-1 invert

(config-route-map)# set community-set comm-set-1 delete

(config-route-map)# exit

(config)#

match community-set

Name

match community-set - specifies a set of BGP communities to be matched

Syntax

match community-set name [exact]? [invert]?

no match community-set name [exact]? [invert]?

Mode

Route Map Configuration

match distance

Route Maps Page 462

Parameters

name - the name of the community set

exact - optionally specify that a community set must be matched exactly. Ordinarily, supersets are

considered to match a community set.

invert - optionally specify to reverse the result of a match

Description

Use the match community-set command to specify a set of BGP communities that you want to be

matched in this route map. If the referenced community set has not yet been configured, then the result is that the match fails.

Note: This command applies only to BGP routes. It will be ignored for all other protocols.

Default

No community sets are matched by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being evaluated against route map "abc" matches interface "fxp1" and the BGP Community labeled "bgpcomm1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in the community set "com-set-2" will be deleted from the matching route.

The metric for the matching route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match community-set bgpcomm1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

match distance

Name

match distance - specifies to match a route’s distance (or preference) in the route map

Syntax

match distance dist [invert]?

no match distance dist [invert]?

Mode

Route Map Configuration

Parameters

dist - an integer from 0 to 255, inclusive

match extended-community-set

Route Maps Page 463

invert - optionally specify to reverse the result of a match

Description

This command specifies to match a route’s preference in this route map.

Default

Distances (or preferences) are not matched by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example configures a route map, xyz, that specifies to match routes with a distance of 10.

(config)# route-map xyz

(config-route-map)# match distance 10

(config-route-map)# exit

(config)#

match extended-community-set

Name

match community-set - specifies a set of BGP extended communities to be matched

Syntax

match extended-community-set name [exact]? [invert]?

no match extended-community-set name [exact]? [invert]?

Mode

Route Map Configuration

Parameters

name - the name of the community set

exact - optionally specify that a community set must be matched exactly. Ordinarily, supersets are

considered to match a community set.

invert - optionally specify to reverse the result of a match

Description

Use the match extended-community-set command to specify a set of BGP extended communities that

you want to be matched in this route map. If the referenced extended community set has not yet been configured, then the result is that the match fails.

Note: This command applies only to BGP routes. It will be ignored for all other protocols.

Default

No extended community sets are matched by default.

Command History

NGC 2.2 - This command was introduced.

match instance

Route Maps Page 464

Examples

In the following example, if the route being evaluated against route map "abc" matches interface "fxp1" and the BGP Extended Community labeled "extcomm1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in the community set "com-set-2" will be deleted from the matching route.

The metric for the matching route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match extended-community-set extcomm1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

match instance

Name

match instance - specifies an OSPF instance to be matched by a route map

Syntax

match instance instance-id [invert]?

no match instance instance-id [invert]?

Mode

Route Map Configuration

Parameters

instance-id - an integer from 1 to 65535, inclusive, specifying an OSPF instance

invert - optionally specify to reverse the result of a match

Description

Use the match instance command to specify an OSPF instance to be matched. Note: This command

applies only to OSPF. It will be ignored for all other protocols.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches instance 1, then the route will only be exported to level 1.

(config)# route-map abc

(config-route-map)# match instance 1

(config-route-map)# set level 1

match interface

Route Maps Page 465

match interface

Name

match interface - specifies an interface or set of interfaces to be matched

Syntax

match interface [interface_name | all | ip_address] [invert]? {1,n}

no match interface [interface_name | all | ip_address] [invert]? {1,n}

Mode

Route Map Configuration

Parameters

interface_name - specify the physical interface name

all - specify to include match all interfaces

ip_address - specify a valid IPv4 logical interface address

invert - optionally specify to reverse the result of a match

{1,n} - You can use this command an unlimited number of times to specify an unlimited number of

interfaces

Description

Use match interface to specify an interface or set of interfaces that you want to be matched in this route

map.

Default

This option is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being evaluated against route map "abc" matches interface "fxp1" and the AS path list labeled "list1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The metric for the matching route will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match as-path-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

match ip address access-list

Route Maps Page 466

match ip address access-list

Name

match ip address access-list - specifies an access list to be matched in this route map

Syntax

match ip address access-list name [invert]?

no match ip address access-list name [invert]?

Mode

Route Map Configuration

Parameters

name - the name of the access list to be matched

invert - optionally specify to reverse the result of a match

Description

Use the match ip address access-list command to specify an access list that you want to be matched

in this route map. If the referenced access list has not yet been configured, then the result is that the match fails.

Default

Access list matches are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the prefix list labeled, "list1" and the access list labeled "list1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The MED for routes will be set to 1.

(config)# route-map abc

(config-route-map)# match ip address prefix-list list1

(config-route-map)# match ip address access-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 1

(config-route-map)# exit

(config)#

match ip address prefix-list

Name

match ip address prefix-list - specifies a prefix list to be matched in this route map

match ip address prefix-tree

Route Maps Page 467

Syntax

match ip address prefix-list name [invert]?

no match ip address prefix-list name [invert]?

Mode

Route Map Configuration

Parameters

name - the name of the prefix list to be matched

invert - optionally specify to reverse the result of a match

Description

Use the match ip address prefix-list command to add a prefix list that you want to be matched in

this route map. If the referenced prefix list has not yet been configured, then the result is that the match fails.

Default

Prefix list matches are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the prefix list labeled, "list1" and the access list labeled "list1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The MED for the matching route will be set to 1.

(config)# route-map abc

(config-route-map)# match ip address prefix-list list1

(config-route-map)# match ip address access-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 1

(config-route-map)# exit

(config)#

match ip address prefix-tree

Name

match ip address prefix-tree - specifies a prefix tree to be matched in this route map

Syntax

match ip address prefix-tree name [invert]?

no match ip address prefix-tree name [invert]?

Mode

Route Map Configuration

match ip gateway

Route Maps Page 468

Parameters

name - the name of the prefix tree to be matched

invert - optionally specify to reverse the result of a match

Description

Use the match ip address prefix-tree command to add a prefix tree that you want to be matched in

this route map. If the referenced prefix tree has not yet been configured, then the result is that the match fails.

Default

Prefix tree matches are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the prefix tree labeled, "tree1" and the access list labeled "list1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The MED for the matching route will be set to 1.

(config)# route-map abc

(config-route-map)# match ip address prefix-tree tree1

(config-route-map)# match ip address access-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 1

(config-route-map)# exit

(config)#

match ip gateway

Name

match ip gateway - specifies a gateway to be matched

Syntax

match ip gateway ipv4_address [invert]?

no match ip gateway ipv4_address [invert]?

Mode

Route Map Configuration

Parameters

ip_address - specifies a valid IPv4 logical address for the gateway

invert - optionally specify to reverse the result of a match

match ip next-hop

Route Maps Page 469

Description

Use the match ip gateway command to match IPv4 gateways and to specify those gateway addresses.

Default

Gateway values are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies to match gateway 1.2.3.4 in route map abc.

(config)# route-map abc

(config-route-map)# match ip gateway 1.2.3.4

(config-route-map)# exit

(config)#

match ip next-hop

Name

match ip next-hop - specifies to match a nexthop address in a route map

Syntax

match ip [bgp]? next-hop [ipv4_address | all] [invert]?

no match ip [bgp]? next-hop [ipv4_address | all] [invert]?

Mode

Route Map Configuration

Parameters

bgp - optionally specify to match a BGP nexthop address in the route map

ipv4_address - specifies a valid IPv4 logical address for the nexthop

all - specifies that all nexthops of a route must match

invert - optionally specify to reverse the result of a match

Description

Use the match ip next-hop command to specify the IPv4 nexthop address to be matched.

Default

Nexthop values are not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example specifies to match nexthop 1.2.3.4 in route map abc.

(config)# route-map abc

(config-route-map)# match ip next-hop 1.2.3.4

match ip route-source prefix-tree

Route Maps Page 470

(config-route-map)# exit

(config)#

match ip route-source prefix-tree

Name

match ip route-source prefix-tree - specifies the name of a prefix tree to be matched

Syntax

match ip route-source prefix-tree name [invert]?

no match ip route-source prefix-tree name [invert]?

Mode

Route Map Configuration

Parameters

name - the name of the prefix-tree to be matched

invert - optionally specify to reverse the result of a match

Description

Use match ip route-source prefix-tree to specify prefix trees that you want to be matched in the

associated route map. If the referenced prefix tree has not yet been configured, then the result is that the match fails.

Default

Prefix tree matches are not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the community list labeled, "list1" and the prefix tree labeled "tree1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The MED for the matching route will be set to 1.

(config)# route-map abc

(config-route-map)# match ip route-source prefix-tree tree1

(config-route-map)# match community list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

(config-route-map)# set metric 1

(config-route-map)# exit

(config)#

match localpref

Route Maps Page 471

match localpref

Name

match localpref - specifies a BGP Local_Pref value to be matched

Syntax

match localpref value [invert]?

no match localpref value [invert]?

Mode

Route Map Configuration

Parameters

value - an integer from 0 to 4,294,967,295, inclusive

invert - optionally specify to reverse the result of a match

Description

Use the match localpref command to filter BGP routes with a specific Local_Pref value.

Note: This command applies only to BGP routes. It will be ignored for any other protocol.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route has a BGP Local Preference value of 20, then the MED will be set to 1.

(config)# route-map abc

(config-route-map)# match localpref 20

(config-route-map)# set med 1

(config-route-map)# exit

match med

Name

match med - specifies a BGP Multi-Exit Discriminator (MED) to be matched

Syntax

match med value [invert]?

no match med value [invert]?

Mode

Route Map Configuration

Parameters

value - an integer from 0 to 4,294,967,295, inclusive

match metric

Route Maps Page 472

invert - optionally specify to reverse the result of a match

Description

Use the match med command to specify a BGP MED value to be matched. Note: This command applies

only to BGP. It will be ignored for all other protocols.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route has a BGP MED value of 20, then the Local Pref value will be set to 1.

(config)# route-map abc

(config-route-map)# match med 20

(config-route-map)# set local-preference 1

(config-route-map)# exit

match metric

Name

match metric - specifies a route metric to be matched

Syntax

match metric value [invert]?

no match metric value [invert]?

Mode

Route Map Configuration

Parameters

value - an integer from 0 to 4,294,967,295, inclusive

invert - optionally specify to reverse the result of a match

Description

Use the match metric command to specify a route’s metric value to be matched.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route has a metric value of 4, then the preference will be set to 50.

(config)# route-map xyz

(config-route-map)# match metric 4

match metric-type

Route Maps Page 473

(config-route-map)# set preference 50

(config-route-map)# exit

(config)#

match metric-type

Name

match metric-type - compares the metric types for OSPF

Syntax

match metric-type [type-1 | type-2] [invert]?

no match metric-type [type-1 | type-2] [invert]?

Mode

Route Map Configuration

Parameters

type-1 - specifies to match the OSPF external type 1 metric

type-2 - specifies to match the OSPF external type 2 metric

invert - optionally specify to reverse the result of a match

Description

Use the match metric-type command when comparing metric types for OSPF. The meanings are

specific to each protocol.

Note: You cannot include more than one parameter for a single match metric-type command

Default

If match metric-type is not specified, it is the same as if the user had specified the following

for OSPF: (config-route-map)# match metric-type type-2

Command History

NGC 2.2 - This command was introduced.

match protocol

Name

match protocol - specifies a protocol to be matched

Syntax

match protocol proto [invert]?

match protocol proto [invert]?

Mode

Route Map Configuration

match ribs

Route Maps Page 474

Parameters

proto - specifies a protocol to be matched. Valid values include the following:

aggregate – Aggregate routes

all – All protocols

bgp – BGP routes

direct – Directly connected routes

kernel – Kernel routes

ospf – OSPF routes

ospf-ase – OSPF ASE routes

ospf3-ase – OSPFv3 ASE routes

rip – RIP routes

ripng – RIPng routes

static – Static routes

invert - optionally specify to reverse the result of a match

Description

Use the match protocol command to specify routes from a specific protocol to be matched.

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route is a BGP route, then the preference will be set to 50.

(config)# route-map xyz

(config-route-map)# match protocol bgp

(config-route-map)# set preference 50

(config-route-map)# exit

(config)#

match ribs

Name

match ribs - specifies RIBs to be matched

Syntax

match ribs [unicast || multicast] [invert]?

no match ribs [unicast || multicast] [invert]?

Mode

Route Map Configuration

Parameters

unicast - specifies unicast RIB

match tag

Route Maps Page 475

multicast - specifies multicast RIB

invert - optionally specify to reverse the result of a match

Description

Use the match ribs command to limit the match to a set of either unicast and/or multicast RIBs. By default,

a route map applies to all RIBs to which any contributing route applies. For example, a route map applies to the Unicast RIB if and only if any contributing route applies to the Unicast RIB.

Note: If a set ribs command is not specified, then no action is taken if the routes match.

Default

If match ribs is not specified, it is as if the user had specified the following:

(config)# match unicast multicast

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes routes in the unicast RIB to be exported into both the unicast and multicast RIBs.

(config)# route-map abc

(config-route-map)# match ribs unicast

(config-route-map)# set ribs multicast

(config-route-map)# set ribs unicast

match tag

Name

match tag - specifies the tag value with which routes are announced in OSPFASE, RIP, or RIPng

Syntax

match tag tag_value [invert]?

no match tag tag_value? [invert]?

Mode

Route Map Configuration

Parameters

tag_value - an integer from 0 to 4,294,967,295, inclusive

invert - optionally specify to reverse the result of a match

Description

Use the match tag command specifies a tag value with which routes are announced in OSPFASE, RIP, or

RIPng. The negative form of this command, no match tag, removes the configured tag_value and returns

this to its default value of 0.

Notes:

Specifying a value for tag_value in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

This command will be ignored for any protocol that is not OSPFASE, RIP, or RIPng.

route-map

Route Maps Page 476

Default

If match tag is not specified, it is the same as if the user had specified the following:

(config-route-map)# match tag 0

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if routes are announced with a tag value of 4, then when this route map is imported into a protocol, the preference for that protocol will be configured as 50.

(config)# route-map abc

(config-route-map)# match tag 4

(config-route-map)# set preference 50

(config-route-map)# exit

(config)#

route-map

Name

route-map - enters route-map configuration mode for a specified route map

Syntax

route-map name [permit | deny]? [seq_value]?

no route-map name [permit | deny]? [seq_value]?

Mode

Global Configuration

Parameters

name - a string of characters that identifies this route map

permit | deny - accepts or rejects routes matching this route map. If neither is specified, this option

defaults to permit.

seq_value - an integer indicating the position a new route map is to have in a list of previously configured

route maps

Description

The route-map command specifies the name of a route map and optionally whether to permit or deny

routes matching the route map. A sequence number can also be specified. Specifying this command enters you in Route Map Configuration mode, where further commands can be specified.

Default

Route maps are not configured by default. When one is configured, however, the default behavior is to permit the route map.

Command History

NGC 2.2 - This command was introduced.

set as-path prepend

Route Maps Page 477

Examples

The following configuration enters Route Map Configuration mode for route map abc.

(config)# route-map abc

(config-route-map)#

set as-path prepend

Name

set as-path prepend - specifies a series of AS numbers to be prepended to a route’s AS_PATH before

announcement

Syntax

set as-path prepend as_number

no set as-path prepend as_number

Mode

Route Map Configuration

Parameters

as_number - an AS number or list of AS numbers specified using integers. The value range is 0 to 65535,

inclusive.

Description

Use the set as-path prepend command to specify a series of AS numbers to be prepended to a route’s

AS_PATH before announcement. These AS numbers are included in a lending sequence of the type appropriate for the peer they are being sent to.

Note: This command applies only to BGP. It will be ignored for all other protocols.

Default

The set as-path prepend command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if a route matches AS Path list "alist1", then the numbers 655 will be prepended to a route’s AS_PATH before announcement, and the origin advertised to BGP will be "incomplete".

(config)# route-map xyz

(config-route-map)# match as-path-list alist1

(config-route-map)# set as-path prepend 655

(config-route-map)# set origin incomplete

(config-route-map)# exit

(config)#

set community-set

Route Maps Page 478

set community-set

Name

set community-set - specifies a community set that should be added to a route, removed from a route,

or overwritten

Syntax

set community-set name [extended]? [delete | additive? | overwrite]

no set community-set name [extended]? [delete | additive | overwrite]?

Mode

Route Map Configuration

Parameters

name - the name of a community set

extended - specifies that the referenced community set is of the extended type

delete - removes a set of communities or extended communities from a route

additive - adds a set of communities or extended communities to a route. Because this is the default

action, specifying this is optional.

overwrite - specifies that the community set overwrites any communities received with the route

Description

Use the set community-set command to specify a community set in a route map and whether that

community set should be added to a route, deleted from a route, or overwritten. The negative form of this

command, no set community-set, removes the configured list from the actions to take in this route map.

Notes:

This command applies only to BGP.

Specifying an argument for the community set name in the no form of this command has no effect

on the configuration. Thus, delete, additive, and overwrite are displayed above as optional.

Default

Community sets are not explicitly added to this route map by default. If one is configured, however, the

default action is additive.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being evaluated against route map "abc" matches interface "fxp1" and the AS path list labeled "list1", then the following set actions will be executed:

Communities specified in community set "com-set-1" will be added to the matching route.

Communities specified in community set "com-set-2" will be deleted from the matching route.

The metric for routes will be set to 50.

(config)# route-map abc

(config-route-map)# match interface fxp1

(config-route-map)# match as-path-list list1

(config-route-map)# set community-set com-set-1 additive

(config-route-map)# set community-set com-set-2 delete

set dampen-flap

Route Maps Page 479

(config-route-map)# set metric 50

(config-route-map)# exit

(config)#

set dampen-flap

Name

set dampen-flap - specifies the name of a route flap dampening configuration to be matched

Syntax

set dampen-flap name

no set dampen-flap name

Mode

Route Map Configuration

Parameters

name - a string of characters specifying a dampen flap

Description

In order for any damping to take place, routes must match against a route map that specifies damping

parameters. The set dampen-flap command specifies a dampen flap that contains these parameters.

Default

The set dampen-flap command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if a route matches AS path list "list1", then damping will occur as specified by the parameters in the dampen flap named rfd1.

(config)# route-map abc

(config-route-map)# match as-path-list list1

(config-route-map)# set dampen-flap rfd1

(config-route-map)# exit

(config)#

set ip next-hop

Name

set ip next-hop - specifies the nexthop with which a BGP route is to be advertised

Syntax

set ip next-hop ipv4_address

no set ip next-hop ipv4_address

set local-preference

Route Maps Page 480

Mode

Route Map Configuration

Parameters

ipv4_address - a valid IPv4 address in dotted-quad format

Description

Use the set ip next-hop command to specify the nexthop with which a BGP route is to be advertised.

Note: This command only applies to BGP. It will be ignored for all other protocols.

Default

BGP will not modify the nexthop value by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if a route matches AS path list "list1", then the nexthop when the route is announced by BGP will be 192.10.2.1.

(config)# route-map abc

(config-route-map)# match as-path-list list1

(config-route-map)# set ip next-hop 192.10.2.1

(config-route-map)# exit

(config)#

set local-preference

Name

set local-preference - sets a route’s local preference

Syntax

set local-preference num

no set local-preference num?

Mode

Route Map Configuration

Parameters

num - an integer from 0 to 4,294,967,295, inclusive

Description

Use the set local-preference command to set a route’s BGP Local Preference value. The negative

form of this command, no set local-preference, removes the configured num value.

Notes:

This command applies only to BGP routes. It will be ignored for all other routes.

Specifying a value for num in the no form has no effect on the configuration. Thus, it is displayed

above as optional.

set med

Route Maps Page 481

Default

This command is not explicitly configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the AS Path list labeled "aspathlist1", then the local preference value will be set to 10.

(config)# route-map abc

(config-route-map)# match as-path-list aspathlist1

(config-route-map)# set local-preference 10

(config-route-map)# exit

set med

Name

set med - specifies the MED with which a matching route will be announced

Syntax

set med [ +value | +igp | value | igp ]

no set med [ +value | +igp | value | igp ]

Mode

Route Map Configuration

Parameters

+value - an integer to be added to the route’s current MED. This value can be from 0 to 4,294,967,295,

inclusive.

value - an integer to be used as the routes’s MED. This value can be from 0 to 4,294,967,295, inclusive.

+igp - specifies to add the route’s IGP metric to the MED

igp - specifies to use the routes IGP metric as the MED

Description

Use the set med command to change or configure a MED value with which a route will be announced if a

match occurs in this route map. Note: This command only applies to BGP. It will be ignored for all other protocols.

Default

The MED value is not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the AS Path list labeled "aspathlist1", then the MED will be set to 1.

(config)# route-map abc

set metric

Route Maps Page 482

(config-route-map)# match as-path-list aspathlist1

(config-route-map)# set med 1

(config-route-map)# exit

(config)#

set metric

Name

set metric - specifies the metric with which a matching route will be announced

Syntax

set metric value

no set metric value

Mode

Route Map Configuration

Parameters

value - an integer

Description

Use the set metric command to change or configure a metric with which a route will be announced if a

match occurs in this route map. Note: This command has no effect on BGP routes.

Default

The metric value is not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route matches the AS Path list labeled "aspathlist1", then the metric will be set to 1.

(config)# route-map abc

(config-route-map)# match as-path-list aspathlist1

(config-route-map)# set metric 1

(config-route-map)# exit

(config)#

set metric-type

Name

set metric-type - configures the metric types for OSPF and BGP

Syntax

set metric-type [internal | type-1 | type-2]

set origin

Route Maps Page 483

no set metric-type [internal | type-1 | type-2]

Mode

Route Map Configuration

Parameters

internal - specifies that BGP should use IGP metrics as the MED value

type-1 - specifies OSPF external type 1 metric

type-2 - specifies OSPF external type 2 metric

Description

Use the set metric-type command to configure metric types for OSPF and BGP. The meanings are

specific to each protocol.

Note: You cannot include more than one parameter for a single set metric-type command

Default

If set metric-type is not specified, it is the same as if the user had specified the following

for OSPF: (config-route-map)# set metric-type type-2

for BGP: (config-route-map)# no set metric-type internal

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if routes are announced with a tag value of 4, then when this route map is imported into a protocol, the metric-type for OSPF routes will be configured as type-2.

(config)# route-map abc

(config-route-map)# match tag 4

(config-route-map)# set metric-type type-2

(config-route-map)# exit

(config)#

set origin

Name

set origin - sets the origin attribute on matching routes to be advertised to BGP

Syntax

set origin [egp | igp | incomplete]

no set origin [egp | igp | incomplete]

Mode

Route Map Configuration

Parameters

egp - specifies routes learned from the EGP protocol. This path is most likely not complete.

igp - specifies routes learned from an Intra-Domain Routing Protocol. This path is most likely complete.

incomplete - specifies routes learned from a source other than IGP and EGP

set preference

Route Maps Page 484

Description

Use the set origin command to configure the origin attribute on matching routes to be advertised to BGP

when this route is exported. An origin of igp indicates the route was learned from an Intra-Domain Routing

Protocol and is most likely complete. An origin of egp indicates the route was learned from the EGP

protocol, and the path is most likely not complete. When the route is learned from another source, an origin

of incomplete is used.

Notes:

This command applies only to BGP.

Some competitors set the BGP ORIGIN attribute differently on routes configured via the static statement (origin incomplete) than via the BGP network statement (origin IGP). Advanced Routing Suite always sets origin incomplete. Use the "set origin" ("set origin" on page 483) Route Map command to modify the origin.

Default

The set origin command is not configured by default.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if a route matches AS Path list "as-path-list1", then the numbers 655 will be prepended to the route’s AS_PATH before announcement, and the origin will be set to "incomplete".

(config)# route-map xyz

(config-route-map)# match as-path-list as-path-list1

(config-route-map)# set as-path prepend 655

(config-route-map)# set origin incomplete

(config-route-map)# exit

(config)#

set preference

Name

set preference - configures the Advanced Routing Suite preference on routes matching this route map

Syntax

set preference pref

no set preference pref

Mode

Route Map Configuration

Parameters

pref - an integer between 1 and 255, inclusive

Description

Use the set preference command to configure the Advanced Routing Suite preference on routes that

match this route map.

set propagate

Route Maps Page 485

Default

The default preference value is the preference value of the protocol.

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if a route’s AS Path matches the AS Path list labeled "aspathlist1", then the preference will be set to 50.

(config)# route map abc

(config-route-map)# match as-path-list aspathlist1

(config-route-map)# set preference 50

(config-route-map)# exit

(config)#

set propagate

Name

set propagate - specifies whether type-7 (nssa) routes get translated into type-5 routes on the backbone

Syntax

set propagate

no set propagate

Mode

Route Map Configuration

Parameters

none

Description

Use the set propagate command to specify whether type-7 (nssa) routes get translated into type-5 routes

on the backbone. If the flag is not set on a route, then it is not translated.

Note: This command applies only to OSPF. It will be ignored for all other protocols.

Default

If set propagate is not specified, it is the same as if the user had specified the following:

(config-route-map)# no set propagate

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if the route being evaluated against route map "abc" matches the BGP Community List "commlist1" and the AS path list labeled "aspathlist1", then exported routes will be propagated.

(config)# route-map abc

(config-route-map)# match community commlist1

(config-route-map)# match as-path-list aspathlist1

set ribs

Route Maps Page 486

(config-route-map)# set propagate

(config-route-map)# exit

(config)#

set ribs

Name

set ribs - specifies the RIBs into which a route will be imported or from which a route will be exported

Syntax

set ribs [ unicast | multicast ]

no set ribs [ unicast | multicast ]

Mode

Route Map Configuration

Parameters

unicast - specifies unicast RIB

multicast - specifies multicast RIB

Description

Use the set ribs command to specify the RIBs into which a route will be imported or from which a route

will be exported.

Default

By default, a route map applies to all RIBs.

Command History

NGC 2.2 - This command was introduced.

Examples

The following example causes routes in the unicast RIB to be exported into both the unicast and multicast RIBs.

(config)# route-map abc

(config-route-map)# match ribs unicast

(config-route-map)# set ribs unicast

(config-route-map)# set ribs multicast

(config-route-map)# exit

(config)#

set tag

Name

set tag - specifies the tag value with which routes will be announced into OSPFASE, RIP, or RIPng

set tag

Route Maps Page 487

Syntax

set tag tag_value

no set tag tag_value?

Mode

Route Map Configuration

Parameters

tag_value - a 32-bit value for the tag specified using a decimal (base 10) number

Description

Use the set tag command to propagate tag data from an exterior gateway protocol (such as BGP) through

OSPFASE, RIP, or RIPng. The negative form of this command, no set tag, removes the configured

tag_value and returns this to its default value of 0.

Notes:

Specifying a value for tag_value in the no form has no effect on the configuration. Thus, it is

displayed above as optional.

This command will be ignored for any protocol that is not OSPFASE, RIP, or RIPng.

Default

If set tag is not specified, it is the same as if the user had specified the following:

(config-route-map)# set tag 0

Command History

NGC 2.2 - This command was introduced.

Examples

In the following example, if routes are received with a tag value of 4, then when a matching route is imported into a protocol, the preference for that route will be configured as 50, and the new tag value will be 5.

(config)# route-map abc

(config-route-map)# match tag 4

(config-route-map)# set preference 50

(config-route-map)# set tag 5

(config-route-map)# exit

(config)#

Index A

Aborting an Executing Command • 20 About this Guide • 13 Access Lists • 417 Access Lists Overview • 417 access-list • 417 access-list sequence-number • 419 Address and Prefix Formats • 38 address-family • 76 advertise-subnet • 171, 222 aggregate-address • 443 allow-all • 223 area advertise-subnet • 199 area authentication • 200 area dead-interval • 202 area filter • 203 area hello-interval • 204 area nssa • 205 area nssa-range • 206 area nssa-translate-always • 207 area poll-interval • 208 area priority • 209 area range • 210 area retransmit-interval • 211 area stub • 212 area stubhost • 213 area stubnetwork • 214 area transmit-delay • 215 area virtual-link • 216 AS Paths and AS Path Lists • 426 AS Paths and AS Path Lists Overview • 426 Assigning Preferences • 39 authentication • 172, 223 autonomous-system • 41

B

Basic Features • 18 bgp always-compare-med • 77 bgp as-path-loops • 77 bgp bestpath as-path ignore • 78 bgp bestpath compare-cluster-list-length • 79 bgp bestpath compare-originator-id • 80 bgp bestpath compare-router-id • 80 bgp bestpath med confed • 81 bgp bestpath med missing-as-worst • 82 bgp cluster-id • 83 BGP Communities and Community Lists • 432 BGP Communities and Community Lists

Overview • 432 bgp confederation identifier • 84 bgp confederation peers • 84 bgp non-leading-confeds • 85 bgp open-on-accept • 86 bgp pass-optional-nontrans • 87 bgp restart-defer • 88 bgp restart-delete-remnants • 89 bgp restart-time • 89 bgp restart-timeout • 90 bgp router-id • 91

bgp send-group-always • 92 bgp tie-break-on-age • 92 Border Gateway Protocol (BGP) • 70 Border Gateway Protocol (BGP) Overview • 72

C

clear ip bgp • 93 clear ip igmp group • 332 clear ip mroute • 62 CLI Behavior Commands • 22 CLI Modes • 20 Command History • 15 Command Line Completion • 18 Command Tokens • 18 compatible rfc1583 • 174 configure file • 22 configure terminal • 22 Context-Sensitive Help • 19 cost • 225

D

dampen-flap • 448 dead-interval • 174, 226 Default • 15, 17 default-metric • 94, 217, 280 default-nssa-metric • 218 default-nssa-type • 219 default-preference • 219 default-tag • 220 default-type • 221 Description • 15, 22, 23, 24, 25, 26, 27, 28, 29,

30, 31, 32, 36 disable • 23, 42 Disabling/Enabling CLI Tracing • 20 distance • 95, 175 Distance Vector Multicast Routing Protocol

(DVMRP) • 316 Distance Vector Multicast Routing Protocol

(DVMRP) Overview • 316 distribute-list • 96, 281

E

ecmp • 284 enable • 23, 97, 176, 227, 284 enable-te • 177 end • 24 Example 1 • 27 Example 2 • 27 Example 3 • 296, 310 Examples • 15, 22, 23, 24, 25, 26, 27, 28, 29,

30, 31, 32, 36 exit • 24 Exiting the CLI • 20

F

Fast Open Shortest Path First (OSPF) • 164 Fast Open Shortest Path First (OSPF)

Overview • 166 Field Descriptions • 32, 36 flash-update-time • 285

G

General Concepts • 38 Global Configuration M ode • 21

Page 490

H

hello-interval • 178, 228 History • 20 How CLI Commands are Documented in this

Guide • 13

I

ignore-host-routes • 286 ignore-must-be-zero • 287 igp-shortcut • 179 inherit-metric • 180 Interface Configuration M ode • 21 Interfaces • 41 Interfaces Overview • 41 Internet Control Message Protocol (ICMP) • 160 Internet Control Message Protocol (ICMP)

Overview • 160 Internet Group Management Protocol (IGMP) •

331 Internet Group Management Protocol (IGMP)

Overview • 331 ip access-list sequence-number • 420 ip access-list standard • 421 ip as-path access-list • 427 ip as-path name • 428 ip community-list • 432 ip community-set • 433 ip dvmrp • 316 ip dvmrp default-metric • 318 ip dvmrp disable • 319 ip dvmrp distance • 317 ip dvmrp metric-offset • 319 ip dvmrp nodvmrpout • 320 ip dvmrp noretransmit • 321 ip dvmrp prune-lifetime • 322 ip dvmrp trace file • 323 ip dvmrp trace flag • 324 ip dvmrp unicast-routing • 325 ip igmp • 333 ip igmp ignore-v1-messages • 334 ip igmp ignore-v2-messages • 334 ip igmp last-member-query-count • 335 ip igmp last-member-query-interval • 336 ip igmp query-interval • 338 ip igmp query-max-response-time • 339 ip igmp require-router-alert • 340 ip igmp robustness • 341 ip igmp send-router-alert • 342 ip igmp startup-query-count • 343 ip igmp startup-query-interval • 344 ip igmp static-group • 346 ip igmp trace file • 347 ip igmp trace flag • 348 ip igmp version • 349 ip multicast boundary • 63 ip multicast ttl-threshold • 63 ip ospf advertise-subnet • 240 ip ospf allow-all • 241 ip ospf area • 241 ip ospf authentication • 242 ip ospf cost • 244 ip ospf dead-interval • 245 ip ospf enable • 246 ip ospf hello-interval • 247

ip ospf neighbor • 248 ip ospf network • 248 ip ospf no-multicast • 249 ip ospf passive-interface • 250 ip ospf poll-interval • 251 ip ospf priority • 252 ip ospf retransmit-interval • 253 ip ospf traffic-eng administrative-weight • 254 ip ospf traffic-eng attribute-flags • 255 ip ospf traffic-eng bandwidth • 256 ip ospf transmit-delay • 256 ip pim assert-holdtime • 360 ip pim associate-msdp • 389 ip pim bsr-admin-scope • 389 ip pim bsr-border • 390 ip pim bsr-candidate • 391 ip pim bsr-candidate global • 392 ip pim bsr-candidate group • 392 ip pim bsr-candidate interval • 393 ip pim bsr-candidate priority • 394 ip pim bsr-holdtime • 395 ip pim dense trace file • 380 ip pim dense trace flag • 381 ip pim dense-mode • 374 ip pim dr-priority • 361 ip pim dr-switch-immediate • 395 ip pim graft-retry-interval • 375 ip pim hello-holdtime • 362 ip pim hello-interval • 362 ip pim jp-holdtime • 363 ip pim jp-interval • 364 ip pim lan-delay • 365 ip pim mrt-interval • 366 ip pim mrt-spt-multiplier • 396 ip pim mrt-stale-multiplier • 366 ip pim override-interval • 367 ip pim probe-interval • 397 ip pim register-suppression-timeout • 398 ip pim require-genid • 376 ip pim rp-address • 398 ip pim rp-candidate • 399 ip pim rp-candidate advertisement-interval • 400 ip pim rp-candidate group • 401 ip pim rp-candidate holdtime • 402 ip pim rp-candidate priority • 402 ip pim rp-switch-immediate • 403 ip pim source-lifetime • 377 ip pim sparse-mode • 404 ip pim state-refresh-capable • 377 ip pim state-refresh-interval • 378 ip pim state-refresh-rate-limit • 379 ip pim state-refresh-ttl • 380 ip pim threshold • 405 ip pim threshold-dr • 406 ip pim threshold-rp • 406 ip pim trace file • 407 ip pim trace flag • 409 ip pim triggered-hello-delay • 368 ip pim whole-packet-checksum • 410 ip prefix-list • 436 ip prefix-list sequence-number • 437 ip prefix-tree • 438 ip redirect • 265 ip rip authentication • 302 ip rip enable • 303

Page 491

ip rip metric-in • 304 ip rip metric-out • 305 ip rip no-receive • 305 ip rip no-send • 306 ip rip secondary-authentication • 307 ip rip version • 308 ip router-discovery address-policy • 270 ip router-discovery enable • 271 ip router-discovery trace file • 271 ip router-discovery trace flag • 272 ip router-id • 24 ip routingtable-id • 25

K

keep-history • 449 kernel background limit • 46 kernel background priority • 47 kernel flash limit • 48 kernel flash type • 49 Kernel Interface • 46 Kernel Interface Overview • 46 kernel no-change • 50 kernel no-flush-at-exit • 50 kernel no-install • 51 kernel remnant-holdtime • 52 kernel routes • 53 kernel trace file • 54 kernel trace flag • 55

L

logout • 25

M

martian • 59 Martian Addresses • 59 Martian Addresses Overview • 59 match aggregate-contributors • 456 match as • 457 match as-path • 457 match as-path-list • 458 match community • 459 match community-set • 460 match distance • 461 match extended-community-set • 462 match instance • 463 match interface • 464 match ip address access-list • 465 match ip address prefix-list • 465 match ip address prefix-tree • 466 match ip gateway • 467 match ip next-hop • 468 match ip route-source prefix-tree • 469 match localpref • 470 match med • 470 match metric • 471 match metric-type • 472 match protocol • 472 match ribs • 473 match tag • 474 max-flap • 450 maximum-routes • 98 Memory Information • 31 Mode • 14, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 monitor-auth-key • 180 Moving About the Command Line • 19

Multicast • 62 Multicast Overview • 62 multicast-rib • 181

N

Name • 14 neighbor • 229 neighbor add-communities • 99 neighbor aggregator-id • 99 neighbor allow • 101 neighbor as-loop • 102 neighbor as-override • 103 neighbor aspath-prepend • 103 neighbor capability orf comm-filter • 104 neighbor capability orf extcomm-filter • 105 neighbor capability orf prefix-filter • 106 neighbor cluster-id • 107 neighbor distance • 108 neighbor dynamic • 109 neighbor enable • 110 neighbor end-of-rib • 110 neighbor export-localpref • 111 neighbor graceful-restart • 112 neighbor ignore-leading-as • 113 neighbor import-localpref • 114 neighbor keep • 115 neighbor keepalives-always • 116 neighbor local-as • 117 neighbor log-up-down • 118 neighbor maximum-routes • 119 neighbor metric-out • 120 neighbor multi-protocol-nexthop • 121 neighbor next-hop-self • 122 neighbor orf comm-list • 123 neighbor orf extcomm-list • 124 neighbor orf prefix-list • 125 neighbor out-delay • 126 neighbor passive • 126 neighbor password • 127 neighbor pedantic • 128 neighbor peer-group • 129 neighbor preference2 • 130 neighbor receive-buffer • 131 neighbor remote-as • 132 neighbor remove-private-as • 133 neighbor route-map • 134 neighbor route-reflector-client • 135 neighbor route-to-peer • 136 neighbor send-buffer • 137 neighbor send-community • 137 neighbor soft-reconfiguration inbound • 138 neighbor timers • 139 neighbor ttl • 140 neighbor update-source • 141 neighbor use-med • 142 neighbor v4-gateway • 143 neighbor version • 144 network • 145, 230, 287 network area • 182 no-multicast • 231 Notation for parameters • 14 nssa-inherit-metric • 183 nssa-stability-interval • 184

Page 492

O

Overview • 14 Overview of the Advanced Routing Suite CLI •

13

P

Parameters • 15, 22, 25, 32, 36 passive-interface • 232 permit | deny • 421 poll-interval • 184, 233 preference • 43, 288 preference2 • 146 Preferences Overview • 38 Prefix Lists and Prefix Trees • 436 Prefix Lists and Prefix Trees Overview • 436 primary-alias • 43 priority • 185, 234 Privileged Execution M ode • 21 Protocol Independent Multicast - Dense Mode

(PIM-DM) • 374 Protocol Independent Multicast - Dense Mode

(PIM-DM) Overview • 374 Protocol Independent Multicast - Sparse Mode

(PIM-SM) • 388 Protocol Independent Multicast - Sparse Mode

(PIM-SM) Overview • 389 Protocol Independent Multicast (PIM) • 359 Protocol Independent Multicast (PIM) Overview

• 359

Q

query-authentication • 289 Querying the Advanced Routing Suite CLI • 31 quit • 26

R

reach-decay • 450 reach-tick • 451 Redirect Processing • 265 Redirect Processing Overview • 265 redistribute • 147, 186, 290 redistribute-nssa • 188 require-vbit • 189 restart-allow-changes • 190 restart-enable • 191 restart-max-sync-time • 192 restart-type • 193 retransmit-interval • 193, 235 reuse-below • 452 Route Aggregation and Generation • 443 Route Aggregation and Generation Overview •

443 Route Flap Damping • 448 Route Flap Damping Overview • 448 Route Maps • 455 Route Maps Overview • 456 route-map • 475 router aggregate • 447 router bgp • 149 Router Configuration Mode • 21 Router Discovery • 269 Router Discovery Overview • 269 router icmp • 160 router ospf • 170

router redirect • 266 router rip • 280 router-discovery lifetime • 273 router-discovery maximum-interval • 274 router-discovery minimum-interval • 275 router-id • 194 Routing Information Protocol (RIP) • 277 Routing Information Protocol (RIP) Overview •

277

S

Screen Paging • 20 See Also • 15 send-updates • 292 set as-path prepend • 476 set community-set • 477 set dampen-flap • 478 set ip next-hop • 478 set local-preference • 479 set med • 480 set metric • 481 set metric-type • 481 set origin • 482 set preference • 483 set propagate • 484 set ribs • 485 set tag • 485 show access-list • 423 show debugging • 26 show history • 27 show ip access-list • 424 show ip as-path-access-list • 429 show ip bgp • 149 show ip bgp instance • 150 show ip bgp neighbors • 151 show ip bgp orf • 152 show ip bgp paths • 153, 430 show ip bgp peer-group • 154 show ip bgp summary • 155 show ip dvmrp interfaces • 326 show ip dvmrp neighbors • 327 show ip dvmrp route • 328 show ip igmp groups • 350 show ip igmp interface • 354 show ip igmp interface-summary • 357 show ip igmp static-groups • 358 show ip mroute • 64 show ip multicast boundary • 65 show ip multicast ttl-threshold • 66 show ip ospf • 257 show ip ospf border-routers • 258 show ip ospf database • 259 show ip ospf interface • 260 show ip ospf neighbor • 260 show ip ospf request-list • 261 show ip ospf retransmission-list • 262 show ip ospf summary-address • 263 show ip ospf virtual-links • 263 show ip pim bsr-router • 411 show ip pim cbsr • 411 show ip pim control-counters • 369 show ip pim dense-mode interface-summary •

383 show ip pim dense-mode mrt • 383 show ip pim dense-mode mrt-summary • 385

Page 493

show ip pim grafts • 386 show ip pim interface • 370 show ip pim neighbor • 372 show ip pim rp • 412 show ip pim rp-candidate • 413 show ip pim rp-hash • 413 show ip pim sparse-mode join-prune xmit • 414 show ip pim sparse-mode mrt • 414 show ip prefix-list • 440 show ip prefix-tree • 441 show ip rip database • 309 show kernel • 56 show running-config • 28 show version • 29 smux password • 312 smux port • 313 smux trace file • 314 smux trace flag • 314 SNMP Multiplexing (SMUX) • 312 SNMP Multiplexing (SMUX) Overview • 312 source-gateways • 294 split-horizon • 295 Starting the Advanced Routing Suite CLI • 16 suppress-above • 453 Syntax • 14, 22, 23, 24, 25, 26, 27, 28, 29, 30,

31, 32, 36

T

Task Information • 36 terminal history • 29 terminal history size • 30 terminal length • 30 term-updates • 296 The -a option • 17 The Advanced Routing Suite • 13 The -e option • 17 The -f option • 17 The -p option • 16 The -s option • 17 timers basic • 297 timers bgp • 155 timers spf • 195 trace file • 67, 157, 161, 196, 266, 298 trace flag • 68, 158, 162, 197, 267, 299 Trace Options • 67 Trace Options Overview • 67 traffic-eng administrative-weight • 236 traffic-eng attribute-flags • 237 traffic-eng bandwidth • 238 transmit-delay • 198, 239 trusted-gateways • 300 tunnel mode dvmrp • 330

U

unnumbered • 44 unreach-decay • 453 User Execution M ode • 20 Using the Advanced Routing Suite CLI • 16

W

write memory • 31